CN110577581A

CN110577581A - Novel antibacterial lipopeptide compound, preparation method and application thereof

Info

Publication number: CN110577581A
Application number: CN201810582004.3A
Authority: CN
Inventors: 何海音
Original assignee: Rambo Pharmaceutical Co
Current assignee: Rambo Pharmaceutical Co
Priority date: 2018-06-07
Filing date: 2018-06-07
Publication date: 2019-12-17

Abstract

The invention discloses a novel antibacterial lipopeptide compound and a medicinal salt thereof, wherein the structural general formula is as follows:

Description

Novel antibacterial lipopeptide compound, preparation method and application thereof

Technical Field

The invention relates to the technical field of medicine preparation, in particular to a lipopeptide compound with an inhibiting effect on vancomycin-resistant microorganisms, penicillin-resistant microorganisms and methicillin-resistant bacteria, and also relates to a preparation method and application of the lipopeptide compound.

Background

The development of increasingly severe resistance of pathogenic bacteria to antibiotics is a major current threat to public health. In recent years, infections caused by drug-resistant gram-positive and drug-resistant gram-negative pathogenic bacteria are increasing, which requires that the research on novel antibiotics is greatly strengthened. Daptomycin (Daptomycin) is a relatively new antibacterial agent used to treat severe systemic infections caused by Gram-positive bacteria, including drug-resistant strains (see Kline, M., Mason, E., Jr., Kaplan S., Lamberth, L., and Johnson, G., synthetic in-vitro activity of LY146032 and eye other antibacterial aggregate Gram-positive bacteria isolated from computer, Journal of antibacterial chemical therapy,1987,20, 203-.

daptomycin is particularly useful in cutaneous and subcutaneous tissue infections caused by Staphylococcus aureus, left endocarditis, osteomyelitis, prosthetic infections, and the like (see Fowler, G.; Boucher, H.; Corey, G.; Daptomycin versastandard thermal for bacterial and endecamatic used by Staphylococcus aureus, N Engl J Med.2006,355, 653-65; Davis, S.; McKinnon, P.; Hall, L.; Pharmacotherapy.2007,27(12), 1611-1618; Steenbergen, J.; J. Alder, J.; Thorne, G. andTly, F.; Daptomycin: a lipopeptide anti-inflammatory for chemical infection, 288, J. supplement, J. gamma. 3. gamma. 3, J. gamma. 3. gamma. 3, J. gamma. alpha. Daptomycin is a cyclic 13-peptide compound produced by actinomycetes that contains a terminal fatty side chain. The results of the study showed that this drug disrupts the Cell membrane function of bacteria in a number of ways and thus has a good inhibitory effect on drug-resistant Staphylococcus aureus (see Pogliano J; Pogliano, N; Silverman, J.; Daptomycin-Mediated reorganisation of Membrane Architecture catalysts, Mislocalization of antibiotic Cell division proteins, Journal of Bacteriology,2012,194(17), 4494-4504; Baltz R.; Daptomycin: mechanisms of action and resistance, and biorational engineering, Current opinion in Chemical biology 2009,13(2), 144-151). Daptomycin, however, does not inhibit strains of enterococci, including Vancomycin-resistant enterococci (VRE), if not bind to other antibiotics, and has limited utility in treating VRE infections (see Moise; PA; Sakoulas G; McKinnell JA; Lamp KC; DePestel DD; Yoon MJ; Reyes K; Zervos MJ; Clinical Outcom of Daptomycin for Vancomycin-resistant Enterococcus bacilli, Clin. Ther.,2015 Jul 1,37(7), 1443. sup. 1453). In particular, in Europe, America and Asia countries, the resistance of enterococci to Daptomycin has been increasing in recent years (see Cleveland, K.; Gelfand, M.; Daptomycin-Nonsusacitib Enterococcal Infections, infection Dis Clin practice, 2013,21, 79-84).

The need for new effective antibiotics against vancomycin, penicillin and methicillin resistant microorganisms is therefore pressing.

Disclosure of Invention

In order to solve the problem that the existing antibiotics have little effect on drug-resistant pathogenic bacteria, the invention aims to provide a lipopeptide compound which has an inhibiting effect on vancomycin-resistant microorganisms, penicillin-resistant microorganisms and methicillin-resistant bacteria. Therefore, the invention also provides a preparation method of the lipopeptide compound.

In order to achieve the purpose, the invention adopts the following technical scheme:

In a first aspect of the present invention, there is provided a novel antibacterial lipopeptide compound and its pharmaceutically acceptable salts, wherein the structural formula is as follows:

Wherein,

X, Y are each independently hydrogen, alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl, or heteroaryl,

Z is hydrogen, alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl or

R₁、R_1aAnd R₆Each independently is hydrogen, alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl, acyl, OH, OR, NHR, OR NR₂R is selected from C₁–C₆Alkyl radical, C₂–C₆Alkenyl radical, C₂–C₆alkynyl, cycloalkyl, cycloalkenyl, aryl orA heteroaryl group;

R₂、R₃、R₄、R₅、R₇、R₈、R₉、R₁₀And R₁₁Each independently is hydrogen, halo, alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl, cyano, isocyano, thiocyano, isothiocyanato, phospho, phosphoryl, sulfate, sulfoxide, sulfonyl, formyl, acyl, amino, imino, amide, acyloxy, thiocarbonyl, alkoxycarbonyl, carboxyl, carboxyamino, hydroxyl, nitro, nitroso, mercapto, alkoxy, acyloxy, OC ═ ORa, OC ═ OORa, OC ═ ONHRa, OC ═ on (ra)₂NHRa or N (Ra)₂(ii) a Wherein Ra may be C₁–C₆Alkyl radical, C₂–C₆Alkenyl radical, C₂–C₆Alkynyl, cycloalkyl, cycloalkenyl, aryl or heteroaryl;

R₁、R_1a、R₂、R₃、R₄、R₅At least one group is not a hydrogen group;

R₆、R₇、R₈、R₉、R₁₀And R₁₁At least one group is not a hydrogen group;

R₁₂、R₁₃、R₁₄Each independently is hydrogen, halogen, C₁–C₂₅Alkyl radical, C₂–C₂₅Alkenyl, cycloalkyl, cycloalkenyl, C₂–C₂₅alkynyl, aryl, heteroaryl, linear or branched polyvinyl- (OCH)₂CH₂) n-, polypropylene- (OCH)₂CH₂CH₂) m-, wherein n and m are integers between 1 and 10;

R₁₅、R₁₆each independently is hydrogen or- (P 'Q'), wherein P 'is selected from alkyl, alkenyl, cycloalkyl or cycloalkenyl and Q' is selected from primary, secondary, tertiary, quaternary amino.

In a second aspect of the present invention, there is provided a novel antibacterial lipopeptide compound and its pharmaceutically acceptable salts, wherein the structural formula is as follows:

R₁、R_1aEach independently is hydrogen, alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl, cyanoacyl, OH, OR, NHR, OR NR₂R is selected from C₁–C₆Alkyl radical, C₂–C₆Alkenyl radical, C₂–C₆alkynyl, cycloalkyl, cycloalkenyl, aryl or heteroaryl;

R₂、R₃、R₄、R₅Each independently is hydrogen, halo, alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl, cyano, isocyano, thiocyano, isothiocyanato, phospho, phosphoryl, sulfate, sulfoxide, sulfonyl, formyl, acyl, amino, imino, amide, acyloxy, thiocarbonyl, alkoxycarbonyl, carboxyl, carboxyamino, hydroxyl, nitro, nitroso, mercapto, alkoxy, acyloxy, OC ═ ORa, OC ═ OORa, OC ═ ONHRa, OC ═ on (ra)₂NHRa or N (Ra)₂(ii) a Wherein Ra may be C₁–C₆Alkyl radical, C₂–C₆Alkenyl radical, C₂–C₆Alkynyl, cycloalkyl, cycloalkenyl, aryl or heteroaryl;

R₁、R_1aAt least one group is not a hydrogen group;

R₁₂、R₁₃、R₁₄Each independently is hydrogen, halogen, C₁–C₂₅Alkyl radical, C₂–C₂₅Alkenyl, cycloalkyl, cycloalkenyl, C₂–C₂₅Alkynyl, aryl, heteroaryl, straight chainOr branched polyvinyl radicals- (OCH)₂CH₂) n-, polypropylene- (OCH)₂CH₂CH₂) m-, wherein n and m are integers between 1 and 10;

In a third aspect of the present invention, there is provided a novel antibacterial lipopeptide compound and its pharmaceutically acceptable salts, wherein the structural formula is as follows:

R₁、R_1aand R₆each independently is hydrogen, alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl, acyl, OH, OR, NHR, OR NR₂R is selected from C₁–C₆Alkyl radical, C₂–C₆Alkenyl radical, C₂–C₆Alkynyl, cycloalkyl, cycloalkenyl, aryl or heteroaryl;

In a fourth aspect of the invention, there is provided a compound of any one of the following formulae RP002 to RP 022:

RP002

RP003

RP004

RP005

RP006

RP007

RP008

RP009

RP010

RP011

RP012

RP013

RP014

RP015

RP016

RP017

RP018

RP019

RP020

RP021

RP022

In a fifth aspect of the invention, there is provided a pharmaceutical composition comprising a compound as described above, a pharmaceutically acceptable salt thereof and one or more pharmaceutically acceptable excipients.

In a sixth aspect of the invention, there is provided the use of a compound as described above for the manufacture of a medicament for combating bacterial infections.

in a seventh aspect of the invention, there is provided a compound of formula (Inter-II) having the general formula:

Wherein:

R₁、R_1aeach independently is hydrogen radical, alkyl, alkenyl, cycloalkyl, cycloalkenylAlkynyl, aryl, heteroaryl, acyl, OH, OR, NHR OR NR₂R is selected from C₁–C₆alkyl radical, C₂–C₆Alkenyl radical, C₂–C₆Alkynyl, cycloalkyl, cycloalkenyl, aryl or heteroaryl;

R₁、R_1a、R₂、R₃、R₄、R₅At least one of which is not a hydrogen radical.

In an eighth aspect of the invention, there is provided the use of a compound of formula (Inter-II) for the preparation of a lipopeptide having antibacterial activity.

Compared with the prior art, the invention has the following beneficial effects: the drug effect of the novel antibacterial lipopeptide compound is obviously superior to that of daptomycin, wherein the MRSA activity of the compounds RP005 and RP012 is about ten times that of daptomycin. RP005 and RP012 also simultaneously exhibit ten-fold greater activity against vancomycin-resistant enterococci (VRE) than daptomycin; the novel bacteriostatic lipopeptide compounds of the invention may be used to treat infections caused by gram-positive bacteria.

Detailed Description

A structural general formula

the novel antibacterial lipopeptide compound comprises three structures which are respectively shown as formulas (I), (II) and (III).

Wherein,

R₂、R₃、R₄、R₅、R₇、R₈、R₉、R₁₀And R₁₁each independently is hydrogen, halo, alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl, cyano, isocyano, thiocyano, isothiocyanato, phospho, phosphoryl, sulfate, sulfoxide, sulfonyl, formyl, acyl, amino, imino, amide, acyloxy, thiocarbonyl, alkoxycarbonyl, carboxyl, carboxyamino, hydroxyl, nitro, nitroso, mercapto, alkoxy, acyloxy, OC ═ ORa, OC ═ OORa, OC ═ ONHRa, OC ═ on (ra)₂NHRa or N (Ra)₂(ii) a Wherein Ra may be C₁–C₆Alkyl radical, C₂–C₆alkenyl radical, C₂–C₆Alkynyl, cycloalkyl, cycloalkenyl, aryl or heteroarylA group;

R₁、R_1aat least one group is not a hydrogen group;

Pharmaceutically acceptable salts of the compounds of the invention may be obtained as metal salts or complexes such as sodium, potassium, aluminum, calcium, iron, magnesium, manganese salts and double salts, other inorganic and Organic salts, or mannich base adducts using methods known to those skilled in the art (see Richard c. larock, comparative Organic Transformations, vchpublishes, 411415,1989). The compounds of the invention may also be obtained as inorganic salts such as hydrochloric acid, hydrobromic acid, hydroiodic acid, phosphoric acid, nitric acid or sulfates; or organic salts such as acetate, benzoate, citrate, cysteine or other amino acids, fumarate, glycolate, maleate, succinate, tartrate, alkylsulfonate or arylsulfonate salts.

Definition of terms

The term "acyl" as used herein is defined as a carbonyl attached to an alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, or heteroaryl group, examples of which include, but are not limited to, acetyl and benzoyl.

"heterocyclyl" means a saturated 3 to 8 membered monocyclic or polycyclic group containing 1 to 3 heteroatoms selected from nitrogen, oxygen and sulfur. Representative examples are pyrrolidinyl, piperidinyl, piperazinyl, morpholinyl, thiomorpholinyl, aziridinyl, tetrahydrofuranyl. Wherein one or more hydrogen atoms may also be substituted with a group selected from acyl, amino, acyloxy, oxo, thiocarbonyl, imino, alkoxycarbonyl, carboxy, carboxamido, cyano, halogen, hydroxy, nitro, mercapto, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, heterocyclyl, aryl, heteroaryl, alkoxy, aryloxy, sulfinyl, sulfonyl, and formyl.

"aryl" means an aromatic group having 6, 10, or 14 carbon atoms, most preferably 6 to 10 carbon atoms, and which may be substituted with 1 to 3 substituents independently selected from halogen, nitro, cyano, alkenyl, hydroxy, alkyl, haloalkyl, alkoxy, benzyloxy, amino, alkylamino, dialkylamino, carboxy, alkoxycarbonyl, methylenedioxy, and the like. In particular, "aryl" is phenyl or naphthyl optionally substituted with 1 to 3 substituents. "aryl" may also represent a part of a group, such as aralkyl and aroyl.

"heteroaryl" refers to 5 to 6 membered aromatic mono-or poly-heterocyclic groups each containing 1 to 4 atoms independently selected from O, N or S. The heteroaryl ring may be optionally substituted with 1 to 3 substituents selected from the group consisting of halogen, cyano, nitro, hydroxy, amino, alkylalkenyl, cycloalkyl, dialkylamino, alkoxy, aryloxy, carboxy, and the like. Non-limiting heteroaryl groups can include: furyl, thienyl, pyridyl, tetrazolyl, imidazolyl, indolyl, thiazolyl, and the like. Benzofuranyl, benzothienyl, and quinolinyl groups may also be included.

"amino" is defined as a group consisting of one nitrogen atom and two to three substituents independently selected from hydrogen, alkyl, cycloalkyl, alkoxycarbonyl, heterocyclyl, alkenyl, aryl, heteroaryl, sulfonyl, and the like. Amino groups can be of four types: (1) an "unsubstituted amino" or primary amino group with two hydrogen groups attached to the nitrogen atom; (2) the amino group is a mono-substituted amino group or a secondary amino group, a hydrogen group is connected to a nitrogen atom, the other hydrogen group is substituted, and the substitutable group can be an alkyl group, an alkenyl group, a cycloalkyl group, a heterocyclic group, an aryl group or a heteroaryl group; (3) "di-substituted amino" or tertiary amino, both hydrogen groups on the nitrogen atom are substituted, and the substitutable group can be alkyl, alkenyl, cycloalkyl, heterocyclic group, aryl or heteroaryl; (ii) a (4) A "trisubstituted amino" or a quaternary amino group, the nitrogen atom bearing three substituents selected from alkyl, alkenyl, cycloalkyl, heterocyclyl, aryl or heteroaryl groups and the like, the quaternary amino group typically bearing a positive charge.

"acyloxy" means an oxygen-containing group adjacent to an acyl group.

"amido" refers to a nitrogen-containing group adjacent to an acyl group.

"alkoxycarbonyl" is defined as a carbonyl group adjacent to an alkoxy or aryloxy group.

"carboxamide group" means a carbonyl group adjacent to an amino group.

"halo" or "halogen" is defined as fluoro, chloro, bromo, or iodo.

"thio" represents a divalent thio group, such as methylthio and phenylthio, attached to a hydrogen radical, alkyl, cycloalkyl, alkenyl, cycloalkenyl, heterocyclyl, aryl or heteroaryl, and the like.

Unless otherwise specified, "alkyl" is defined as a straight or branched chain saturated carbon chain radical of one to about twenty carbon atoms. Preferred alkyl groups are "lower alkyl" groups having from one to about five carbon atoms. Wherein one or more hydrogen atoms may also be substituted with a substituent selected from the group consisting of: acyl, amino, amido, acyloxy, alkoxycarbonyl, carboxy, carboxamido, cyano, halogen, hydroxy, nitro, mercapto, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, heteroaryl (including indolyl or substituted indolyl, etc.), alkoxy, aryloxy, sulfinyl, sulfonyl, oxo (oxo), guanidino, formyl, and amino acid side chains. Examples of alkyl groups include, but are not limited to, methyl, t-butyl, isopropyl, and methoxymethyl.

"alkenyl" is defined as a straight or branched chain group having from 2 to about 20 carbon atoms, preferably from 3 to about 10 carbon atoms, and containing at least one carbon-carbon double bond. Wherein one or more hydrogen atoms may also be substituted with a substituent selected from the group consisting of: acyl, amino, amido, acyloxy, alkoxycarbonyl, carboxy, carboxamido, cyano, halogen, hydroxy, nitro, mercapto, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, heteroaryl (including indolyl or substituted indolyl, etc.), alkoxy, aryloxy, sulfinyl, sulfonyl, formyl, oxo, and guanidino. The double bond portion of the unsaturated hydrocarbon chain may be in either the cis or trans configuration. Examples of alkenyl groups include, but are not limited to, vinyl or phenylvinyl.

The term "alkynyl" denotes a straight or branched chain group having from 2 to about 10 carbon atoms and containing at least one carbon-carbon triple bond. Wherein one or more hydrogen atoms may also be substituted with a substituent selected from the group consisting of: acyl, amino, amido, acyloxy, alkoxycarbonyl, carboxy, carboxamido, cyano, halogen, hydroxy, nitro, mercapto, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, heteroaryl, alkoxy, aryloxy, sulfinyl, sulfonyl, formyl, oxo, and guanidino. Examples of alkynyl groups include, but are not limited to, propynyl.

"cycloalkyl" or "cycloalkyl ring" is defined as a monocyclic, fused or polycyclic group containing a three to twelve membered saturated carbocyclic ring. Preferred cycloalkyl groups should contain a three to eight membered saturated carbocyclic ring system. Wherein one or more hydrogen atoms may also be substituted with a substituent selected from the group consisting of: acyl, amino, amido, acyloxy, alkoxycarbonyl, carboxy, carboxamido, cyano, halogen, hydroxy, nitro, mercapto, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, heteroaryl (including indolyl or substituted indolyl, etc.), alkoxy, aryloxy, sulfinyl, sulfonyl, and formyl. Examples of cycloalkyl groups include, but are not limited to, cyclopropyl, cyclobutyl, cyclohexyl, and cycloheptyl.

"cycloalkenyl" refers to monocyclic, fused or polycyclic groups containing three to twelve membered unsaturated or partially unsaturated carbocyclic rings. Preferred cycloalkenyl groups should contain a three to eight membered unsaturated carbocyclic ring system. Wherein one or more hydrogen atoms may also be substituted with a substituent selected from the group consisting of: acyl, amino, amido, acyloxy, alkoxycarbonyl, carboxy, carboxamido, cyano, halogen, hydroxy, nitro, mercapto, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, heteroaryl (including indolyl or substituted indolyl, etc.), alkoxy, aryloxy, sulfinyl, sulfonyl, and formyl. Examples of cycloalkenyl groups include, but are not limited to, cyclopentenyl, cyclohexenyl, and cycloheptenyl.

"heterocyclyl", "heterocycle" or "heterocyclyl ring" are defined as monocyclic, fused or polycyclic groups containing from three to twelve members which are unsaturated or partially unsaturated, wherein each ring system may contain from 1 to 4 heteroatoms selected from O, N, NH, S. Preferred heterocyclic groups should contain three to seven membered ring systems. Wherein one or more hydrogen atoms may also be substituted with a substituent selected from the group consisting of: acyl, amino, amido, acyloxy, alkoxycarbonyl, carboxy, carboxamido, cyano, halogen, hydroxy, nitro, mercapto, alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, heteroaryl (including indolyl or substituted indolyl), alkoxy, aryloxy, sulfinyl, sulfonyl, and formyl. Examples of heterocyclyl groups include, but are not limited to, morpholinyl, piperidinyl, and pyrrolidinyl.

"alkoxy" is defined as an oxygen-containing group substituted with an alkyl, cycloalkyl, or heterocyclyl group. Examples include, but are not limited to, methoxy, t-butoxy, benzyloxy, and cyclohexyloxy.

"aryloxy" refers to an oxygen-containing group substituted with an aryl or heteroaryl group. Examples include, but are not limited to, phenoxy.

An "amino acid side chain" is defined as any side chain (R group) from a naturally occurring or non-naturally occurring amino acid.

"sulfinyl" is defined as a tetravalent sulfur group substituted with an oxo substituent (oxo) and another second substituent selected from alkyl, cycloalkyl, heterocyclyl, aryl, or heteroaryl.

"sulfonyl" is defined as a hexavalent sulfur group substituted with two oxo substituents (oxo) and another third substituent selected from the group consisting of alkyl, cycloalkyl, heterocyclylaryl or heteroaryl.

"amino protecting group" refers to a group introduced to an amino group by chemical modification for the purpose of increasing selectivity in a chemical reaction, and this group is removed in a subsequent reaction step. (see "Protective Groups in Organic Synthesis" by Theodora W.Greene, John Wiley and Sons, New York, 1981). Examples of amino protecting groups include benzyloxycarbonyl, tert-butoxycarbonyl (Boc), tert-pentyloxycarbonyl, isobornyloxycarbonyl, adamantyloxycarbonyl, chlorobenzyloxycarbonyl and nitrobenzyloxycarbonyl.

By "pharmaceutically acceptable salt" is meant any salt of the compounds provided herein that retains its biological properties and is non-toxic and non-side-effect for pharmaceutical use. Such salts may be derived from a variety of organic and inorganic counterions known in the art.

the terms "compound," "agent," and "drug" are interchangeable.

The term "effective amount" refers to a therapeutically effective amount or a prophylactically effective amount of a drug, drug combination. A "prophylactically effective amount" is an amount effective, at dosages and for periods of time necessary, to achieve the desired prophylactic effect. In certain examples, the prophylactically effective amount is less than the therapeutically effective amount since the prophylactic dose is used in the subject prior to the disorder or at an earlier stage of the disorder. In certain instances, the prophylactically effective amount is similar to, the same as, or more than the therapeutically effective amount. A therapeutically effective amount of a drug is an amount effective to exhibit the desired activity of the drug. The therapeutically effective amount may vary depending on the compound, the condition and its severity and the age, weight, physical condition and responsiveness of the patient.

"treating" or "treatment" refers to curing or ameliorating a physical condition, disorder or clinical symptom, including (1) preventing or delaying the appearance of the condition, (2) reducing or delaying the progression or recurrence of the disease, (3) relieving the disease, i.e., causing the regression of the clinical symptom or sign.

The benefit to the subject to be treated is statistically significant or at least perceptible to the patient or physician.

"about" means a value of. + -. 0.5.

Thirdly, the innovation point of the invention

Some work has been reported in the literature on the structural modification of daptomycin to increase its activity. For example, substitution of the N-terminal decanoyl chain with certain natural and unnatural long chain acyl groups may increase the inhibitory activity of daptomycin against Staphylococcus aureus to some extent (Hill et al, U.S. patent No.6,911,525; Chester et al, U.S. patent No.8,507,647). In addition, substitution of the terminal decanoyl chain-linked tryptophan residue with another amino acid may also increase the activity of daptomycin against staphylococcus aureus to some extent (Leese et al, U.S. patent No.6,767,718).

The daptomycin modification work of the invention is different from the literature, and mainly comprises two aspects.

1) the tryptophan in daptomycin is firstly replaced by tryptophan containing substituent groups;

2) The tryptophan on the lateral chain and the aniline group on the cyclic peptide are simultaneously subjected to structural modification so as to obviously improve the antibacterial activity, in particular to improve the inhibitory activity to drug-resistant staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE).

Preparation of intermediate (Inter-I)

The preparation of the intermediate (Inter-I) can be carried out starting from daptomycin by reaction with, for example, di-tert-butyl dicarbonate, (Boc)₂o reaction, adding a tert-butyloxycarbonyl protecting group (Boc) to the ornithine amino group_，The amino group on the aniline is then alkylated by a reductive amination reaction. The reagent for the reductive amination reaction may be an aldehyde plus sodium cyanoborohydride. In these reactions, using acetaldehyde, formaldehyde and propionaldehyde, aniline can be converted to phNHEt, phNHMe and phNHPr groups, respectively.

specifically, daptomycin (1) is reacted with di-tert-butyl dicarbonate and triethylamine to add a tert-butoxycarbonyl protecting group (Boc) to the ornithine amino group to produce daptomycin-Boc (2).

daptomycin-Boc (2) and formaldehyde, acetaldehyde or propionaldehyde are subjected to reductive amination reaction in the presence of sodium cyanoborohydride at room temperature to alkylate amino on aniline to obtain a compound of formula Inter-I

Wherein: r_1aHydrogen radical; r₁＝CH₃、CH₂CH₃Or CH₂CH₂CH₃。

The reductive amination reaction described above can be carried out using other aldehyde compounds to achieve a change in R₁The object of (a); r in Inter-I_1aThe alkyl group may be substituted by alkylation.

Preparation of intermediate Inter-II

Selectively cleaving the C-terminal amide bond of a tryptophan residue in a compound of formula Inter-I to produce a cyclic peptide intermediate Inter-II containing twelve amino acids.

Reacting the compound of formula Inter-I with o-iodobenzoic acid and guanidine derivatives to obtain a compound of formula Inter-II;

Wherein R is_1a＝R₂＝R₄Hydrogen radical; r₁＝CH₃、CH₂CH₃Or CH₂CH₂CH₃；

The reaction is usually carried out at room temperature. When the guanidine derivative is guanidine hydrochloride, R₃＝R₅Cl; when the guanidine derivative is guanidine hydrofluoride, R₃＝R₅Hydrogen radical; when the guanidine derivative is a mixture of guanidine hydrofluoride and guanidine hydrobromide in a certain proportion and the guanidine hydrofluoride is in excess, R₃＝Br、R₅Hydrogen radical.

r in the above reaction product Inter-II is changed by changing the reaction conditions, for example, by increasing the reaction temperature or increasing the proportion of guanidine hydrobromide, etc₂、R₄And R₅May be substituted by bromo.

R of formula Inter-II₂、R₃、R₄And R₅cl or Br in (1) can be replaced by other groups such as aryl and unsaturated hydrocarbyl groups by Suzuki Coupling Reactions (see Miyaura, Norio; Suzuki, Akira. Palladium-Catalyzed Cross-Coupling Reactions of Organoboron Compounds.chemical reviews.1979,95, 7, 2457-83.) and improvements thereof (see Bing Wang; Hui-Xia Sun; and Zhui-Hua Sun. "A General and effective Suzuki-Miyaura Cross-Coupling Protocol Using week Base and Water: The expression of acetic acid". Eurorojournal of Organic chemistry. Eur.J.Org.Chem.2009,22, 3688-92.) such as aryl and unsaturated hydrocarbyl groups. The latter may be further derivatized by conventional methods.

The invention discloses a method for selectively cutting off C-terminal amido bonds of tryptophan residues in daptomycin and similar analogues. Reacting a compound of formula Inter-I with an ortho-iodobenzoic acid, guanidine derivative to produce a compound of formula Inter-II. Guanidine derivatives are protein denaturants that accelerate the cleavage of peptide chains. When guanidine hydrochloride or guanidine hydrobromide is used, not only is the peptide bond selectively cleaved, but also a reagent for anilino halogenation is provided.

Compounds of formula InterII may also be obtained by biochemical methods of first removing the decanoyl group with a deacylase (see Kreuzman, AJ; Hodges, RL; Swartling, JR; Pohl, TE; Ghag, SK; Baker, PJ; McGilvray D and Yeh, WK; Membrane-associated biochemical B deacylase of aminoplanetagenesis: purification, chromatography, tertiary cloning and enzymatic hydrolysis reaction; Journal of Industrial Microbiology & Biotechnology; 2000,24, 173-. When the guanidine derivative is guanidine hydrochloride or guanidine hydrobromide, anilino halogenation will also occur.

Preparation of Compounds of formula Inter-III

The formulas Inter-III include Inter-III A, Inter-III B, Inter-III C, Inter-III D, Inter-IIIE and Inter-IIIF.

1) Decanoic acid reacts with 1- [ bis (dimethylamino) methylene ] -1H-1,2, 3-triazolo [4,5-b ] pyridinium 3-oxide hexafluorophosphate and triethylamine to obtain a compound shown in a formula (3);

2) And (3) carrying out coupling reaction on the compound of the formula (3) and amino acid to obtain the compound of the formula (Inter-III), wherein the amino acid is 5-methoxy-L-tryptophan, 5-fluoro-L-tryptophan, 1-methyl-L-tryptophan, 2-methyl-L-tryptophan or 5-methyl-L-tryptophan. The obtained product is:

It is clear that in the preparation of the formula Inter-iii, the decanoic acid can be replaced by other straight or branched chain fatty acids, while the amino acid can be replaced by other types of substituted tryptophan or any other amino acid.

Preparation of compounds of formula (I)

The compound of formula (Inter-II) and Inter-III are subjected to coupling reaction to generate the compound of formula (I). The coupling reagent here is 1- [ bis (dimethylamino) methylene ] -1H-1,2, 3-triazolo [4,5-b ] pyridinium 3-oxide Hexafluorophosphate (HATU) plus a weak base such as N, N-diisopropylethylamine (Hunig's base) or 2,4, 6-collidine (TMP), followed by deprotection of the protecting group Boc with trifluoroacetic acid (TFA) in Dichloromethane (DCM).

Eighth, example

In the preparation process of the substance, the high performance liquid chromatography and liquid chromatography-mass spectrometry are used for determining the reaction progress and whether a target product is obtained. For different systems, the parameters associated with hplc and/or hplc are adjusted, as follows for the processing protocol for analysis in different systems.

1) protocol A1-Neg (liquid Mass analysis):

agilent 1100 LC G1956B MSD, negative polarity

Chromatographic column YMC ODS-A150X 4.6mm,5uM,120A

The solvent system is (20-100% acetonitrile/water) + 0.025% formic acid, 0.5ml/min, 15min total.

2) Protocol A1-Pos (liquid Mass analysis):

Agilent 1100 LC- -G1956B MSD, positive polarity

Chromatographic column YMC ODS-A150X 4.6mm,5uM,120A

The solvent system is (20-100% acetonitrile/water) + 0.025% formic acid, 0.5ml/min for 15 min.

3) Protocol a2 (liquid mass analysis):

Agilent 1100 LC- -G1956B MSD, positive polarity

Chromatographic column YMC ODS-A,150X 4.6mm,5uM,120A

The solvent system is (40-100% acetonitrile/water) + 0.1% formic acid, 0.5ml/min for 15 min.

4) Scheme B1 (high performance liquid chromatography):

The instrument is Rainin Dynamax SD-200, UV-1

chromatographic column YMC ODS-A,250X 30mm,10uM,120A

The solvent system (50% acetonitrile/water) + 0.025% formic acid, 3min, (50-85% acetonitrile/water) + 0.025% formic acid for 17min,20ml/min flow rate, observed wavelength 395 nm.

5) Scheme B2 (high performance liquid chromatography):

the instrument is Rainin Dynamax SD-200, UV-1

Chromatographic column YMC ODS-A,250X 30mm,10uM,120A

The solvent system (50% acetonitrile/water) + 0.025% formic acid, 3min, (30-80% acetonitrile/water) + 0.025% formic acid for 17min,20ml/min flow rate, observed wavelength 395 nm.

6) Scheme B3 (high performance liquid chromatography):

the instrument is Rainin Dynamax SD-200, UV-1

chromatographic column YMC ODS-A,250X 30mm,10uM,120A

the solvent system (50% acetonitrile/water) + 0.025% formic acid for 3min, (60-95% acetonitrile/water) + 0.025% formic acid for 17min,20ml/min flow rate, observed at 230nm wavelength.

EXAMPLE 1 preparation of Inter-IA

Boc protection of Ornithine amino group to yield daptomycin-Boc

a mixture of daptomycin (1.0g) and water (6mL) was stirred at room temperature for 1 hour, and the solid was gradually dissolved. To this solution was added triethylamine (600uL), followed by a solution of di-tert-butyl dicarbonate (500mg) in dimethylsulfoxide (DMSO, 2 mL). The resulting suspension was vigorously stirred for 1 hour to give a pale yellow solution, and liquid chromatography showed complete conversion of daptomycin to daptomycin-Boc. Positive ESIMS: m/z 1720.7(MH) +, and daptomycin-Boc (C)₇₇H₁₁₀N₁₇O28) (protocol a 2). The reaction mixture was extracted with ethyl acetate (5mL) to remove unreacted reagents, and the aqueous layer was acidified with acetic acid (800uL), followed by extraction twice with n-butanol (2X 5 mL). The combined n-butanol solutions were evaporated under reduced pressure to yield a yellowish film-like residue, which was purified by high pressure liquid phase (scheme B1, 3 injections) and the 14 minute peak was collected, evaporated under reduced pressure and dried under vacuum to yield daptomycin-Boc (1.12 g) as a powder. The above reaction is repeated.

Step 2 Aminoalkylation of anilines by reductive amination

To a solution of daptomycin-Boc (900mg) in methanol (5mL) was added acetic acid (360uL) followed by 40% ethylAqueous aldehyde (900 uL). The resulting mixture was stirred at room temperature for 5 minutes, then mixed with a solution of sodium cyanoborohydride (360mg) in methanol (2 mL). The reaction solution was stirred at room temperature for 20 minutes and the product was purified by HPLC (scheme B1), the peak was collected for 16 minutes and evaporated in vacuo to give Inter-IA as a yellow powder (954 mg). Positive polarity ESIMS: m/z1748.6(MH)⁺With Inter-IA (C)₇₉H₁₁₄N₁₇O₂₈) Consistent with the theoretical quality of (protocol a 2).

EXAMPLE 2 preparation of Inter-IB

To a solution of daptomycin-Boc (500mg) in methanol (5mL) was added acetic acid (360uL) followed by 37% aqueous formaldehyde (900 uL). The resulting mixture was stirred at room temperature for 5 minutes, then mixed with a solution of sodium cyanoborohydride (360mg) in methanol (2 mL). The reaction solution was stirred at room temperature for 20 minutes and the product was purified using the HPLC phase (scheme B1), the 16 minute peak was collected and evaporated in vacuo to yield Inter-IB as a yellow powder (255 mg). Negative ESIMS: m/z1732.6(M-H)^-With Inter-IB (C)₇₈H₁₁₀N₁₇O₂₈) The theoretical masses of (scheme A1-Neg) were consistent.

EXAMPLE 3 preparation of Inter-IC

To a solution of daptomycin-Boc (500mg) in methanol (2.5mL) was added acetic acid (180uL) followed by 97% propionaldehyde (60 uL). The resulting mixture was stirred at room temperature for 5 minutes, and then mixed with a solution of sodium cyanoborohydride (50mg) in methanol (1 mL). The reaction solution was stirred at room temperature for 20 minutes and then the product was purified by HPLC (scheme B1), the peak was collected for 16 minutes and evaporated in vacuo to yield an Inter-IC as a yellow powder (440 mg). Negative ESIMS: m/z 1760.7(M-H)^-With Inter-IB (C)₈₀H₁₁₄N₁₇O₂₈) The theoretical masses of (scheme A1-Neg) were consistent.

EXAMPLE 4 preparation of Inter-IIA

A mixed powder of Inter-IA (498mg) and o-iodobenzoic acid (1.0g) was placed in a 100mL brown bottle, a solution of guanidine monohydrochloride (1.0g) in acetic acid (40mL) and water (10mL) was added, and the resulting suspension was stirred at room temperature for 16 hours in the dark.

At the end of the reaction, the reaction was filtered and the yellow filtrate was loaded onto a glass chromatography column containing sephadex LH-20 resin (100g) soaked in methanol (350mL) and then eluted with methanol to obtain a yellow band (150 mL). After evaporation under reduced pressure, the residue (380mg) was further purified by high pressure liquid phase (scheme B2), the peak was collected for 13 minutes and lyophilized to give Inter-IIA (55.0mg) as a bright yellow solid. Negative ESIMS: m/z 1474.3(M-H)^-With Inter-IIA (C)₅₈H₈₂C_l2N₁₅O₂₆) The theoretical masses of (scheme A1-Neg) were consistent.

example 5 preparation of Inter-IIB

a mixed powder of Inter-IB (300mg) and o-iodobenzoic acid (300g) was placed in a 100mL brown bottle, a solution of guanidine monohydrochloride (362mg) in acetic acid (13mL) and water (3mL) was added, and the resulting suspension was stirred at room temperature for 16 hours in the dark.

at the end of the reaction, the reaction was filtered and the yellow filtrate was loaded onto a glass chromatography column containing sephadex LH-20 resin (100g) soaked in methanol (350mL) and then eluted with methanol to obtain a yellow band (150 mL). After evaporation under reduced pressure, the residue (100mg) was further purified by high pressure liquid phase (scheme B2), the peak was collected for 13 minutes and lyophilized to give Inter-IIB (30.5mg) as a bright yellow solid. Negative ESIMS: m/z 1460.3(M-H)^-with Inter-IIB (C)₅₇H₈₀C_l2N₁₅O₂₆) Is/are as followsThe theoretical masses are consistent (scheme A1-Neg).

EXAMPLE 6 preparation of Inter-IIC

A mixed powder of Inter-IC (444mg) and o-iodobenzoic acid (300g) was placed in a 100mL brown bottle, a solution of guanidine monohydrochloride (605mg) in acetic acid (16mL) and water (4mL) was added, and the resulting suspension was stirred at room temperature for 16 hours in the dark.

At the end of the reaction, the reaction was filtered and the yellow filtrate was loaded onto a glass chromatography column containing sephadex LH-20 resin (100g) soaked in methanol (350mL) and then eluted with methanol to obtain a yellow band (150 mL). After evaporation under reduced pressure, the residue (150mg) was further purified by high pressure liquid phase (scheme B2), the peak was collected for 13 minutes and lyophilized to give Inter-IIC (79.0mg) as a bright yellow solid. Negative ESIMS: m/z 1488.4(M-H)^-With Inter-IIC (C)₅₉H₈₄C_l2N₁₅O₂₆) The theoretical masses of (scheme A1-Neg) were consistent.

EXAMPLE 7 preparation of Inter-IID

a mixed powder of Inter-IA (508mg) and o-iodobenzoic acid (1.0g) was placed in a 100mL brown bottle, a solution of guanidine monohydrofluoride (1.0g) in acetic acid (40mL) and water (10mL) was added, and the resulting suspension was stirred at room temperature for 7 days in the dark.

At the end of the reaction, the reaction was filtered and the yellow filtrate was loaded onto a glass chromatography column containing sephadex LH-20 resin (100g) soaked in methanol (350mL) and then eluted with methanol to obtain a yellow band (150 mL). After evaporation under reduced pressure, the residue (360mg) was further purified by high pressure liquid phase (scheme B2), and the 11 min peak was collected and lyophilized to give Inter-IID (70.3mg) as a yellow solid. Negative ESIMS: m/z 1406.4(M-H)^-With Inter-IID (C)₅₈H₈₄N₁₅O₂₆) The theoretical masses of (scheme A1-Neg) were consistent.

EXAMPLE 8 preparation of Inter-IIE

A mixed powder of Inter-IA (422mg) and o-iodobenzoic acid (410mg) was placed in a 100mL brown bottle, a solution of guanidine monohydrofluoride (400mg) and guanidine monohydrobromide (43mg,1.3 equiv.) in acetic acid (16mL) and water (4mL) was added, and the resulting suspension was stirred at room temperature for 1.5 hours in the dark.

At the end of the reaction, the reaction was filtered and the yellow filtrate was loaded onto a glass chromatography column containing sephadex LH-20 resin (100g) soaked in methanol (350mL) and then eluted with methanol to obtain a yellow band (150 mL). After evaporation under reduced pressure, the residue (360mg) was further purified by preparative high pressure liquid phase (scheme B2) and the peak was collected for 13 minutes to give Inter-IIE (127.0mg) as a yellow solid after lyophilization. Negative ESIMS: m/z 1484.3(M-H)^-With Inter-IIE (C)₅₈H₈₃BrN₁₅O₂₆) The theoretical masses of (scheme A1-Neg) were consistent.

EXAMPLE 9 preparation of the intermediates 3H- [1,2,3] triazolo [4,5-b ] pyridin-3-yl decanoate, Inter-IIIA, Inter-IIIB, Inter-IIIC, Inter-IIID, Inter-IIIE and Inter-IIIF

Step 13 preparation of H- [1,2,3] triazolo [4,5-b ] pyridin-3-yldecanoate.

to a solution of decanoic acid (200mg) and 1- [ bis (dimethylamino) methylene ] -1H-1,2, 3-triazolo [4,5-b ] pyridinium 3-oxide hexafluorophosphate (HATU, 211mg) in anhydrous DMF (2mL) was added triethylamine (200uL) with stirring, and the resulting solution was further stirred at room temperature for 16 hours. At the end of the reaction, the reaction was purified using the high pressure liquid phase (scheme B3) and freeze dried to give 3H- [1,2,3] triazolo [4,5-B ] pyridin-3-yldecanoate (3) as a waxy solid (160.5 mg).

Step 2 coupling of amino acids to 3 to produce Inter-IIIA, Inter-IIIB, Inter-IIIC, Inter-IIID, Inter-IIIE, and Inter-IIIF.

the amino acids used in these preparative procedures were dissolved in 5% aqueous trifluoroacetic acid (TFA) (10mg/mL) solutions, respectively, and each of the resulting solutions was lyophilized to give the amino acid TFA salt as a white powder, which was more soluble in N, N-Dimethylformamide (DMF).

To a solution of the above amino acid TFA salt (A) and 3(B) in anhydrous DMF (1mL) was added triethylamine (50uL) with stirring. After stirring the resulting solution at room temperature for 1.5 hours, analysis was performed using liquid chromatography coupled with mass spectrometry (scheme a2), and the product was purified by high pressure liquid phase (scheme B1). The reactants, products and experimental data are listed in table 1.

Table 1 reaction conditions for the preparation of Inter-IIIA, Inter-IIIB, Inter-IIIC, Inter-IIID, Inter-IIIE, and Inter-IIIF.

TFA salts of the-amino acids were used for these coupling reactions.

Nuclear magnetic resonance data for Inter-IIIA-Inter-IIIF (500 mhz, deuterated dimethylsulfoxide, chemical shift):

Inter-IIIA:

δ_H 12.55(br,D₂Exchangeable O), 10.65(s, D)₂Exchangeable O), 8.03(D,8.0Hz, D₂o interchangeably), 7.20(d,7.5Hz),7.08(brs),7.03(d,2.0Hz),6.67(dd,7.5,2.0Hz),4.46(ddd,10.0,8.0,4.5Hz),3.76(3H, s),3.11(15.0,4.5Hz),2.96(dd,15.0,10.0Hz), 2.04(2H, m),1.38(2H, m),1.30-1.09(12H, m),8.85(3H, t,6.5 Hz);

Inter-IIIB:

δ_H 12.60(br,D₂Exchangeable O), 10.93(s, D)₂Exchangeable O), 8.03(D,8.0Hz, D₂interchangeable O), 7.31(dd,7.5,5.0Hz),7.27(dd,9.0,2.0Hz),7.20(d,2.0Hz),6.88(ddd,8.5，7.5,2.0Hz),4.44(ddd,10.0,8.0,4.5Hz),3.11(15.0,4.5Hz),2.96(dd,15.0,10.0Hz)，2.04(2H,t,6.5Hz),1.38(2H,m),1.30-1.09(12H,m),8.85(3H,t,6.5Hz)；

Inter-IIIC:

δ_H 12.58(br,D₂Exchangeable O), 8.01(D,8.0Hz, D₂o interchangeably), 7.54(d,7.5Hz),7.36(d,7.5Hz),7.12(dd,7.5,7.5Hz),7.08(brs),7.01(dd,7.5,7.5Hz),4.45(ddd,10.0,8.0,4.5Hz),3.71(3H, s),3.14(15.0,4.5Hz),2.98(dd,15.0,10.0Hz), 2.05(2H, t,6.5Hz),1.40(2H, m),1.30-1.11(12H, m),8.85(3H, t,6.5 Hz);

Inter-IIID:

δ_H 12.52(br,D₂Exchangeable O), 10.70(s, D)₂Exchangeable O), 7.98(D,8.0Hz, D₂O interchangeably), 7.44(d,7.5Hz),7.20(d,7.5Hz),6.95(dd,7.5,7.5Hz),6.90(dd,7.5,7.5Hz),4.42(ddd,10.0,8.0,4.5Hz),3.08(15.0,4.5Hz),2.93(dd,15.0,10.0Hz), 2.30(3H, s),2.04(2H, t,6.5Hz),1.38(2H, m),1.30-1.10(12H, m),8.86(3H, t,6.5 Hz);

Inter-IIIE:

δ_H 12.53(br,D₂Exchangeable O), 10.66(s, D)₂Exchangeable O), 8.00(D,8.0Hz, D₂O interchangeable), 7.29(brs),7.20(d,7.5Hz),7.06(d,2.0Hz),6.88(dd,7.5,2.0Hz),4.44(ddd,10.0,8.0,4.5Hz),3.12(15.0,4.5Hz),2.96(dd,15.0,10.0Hz), 2.37(3H, s),2.04(2H, t,6.5Hz),1.39(2H, m),1.30-1.10(12H, m),8.85(3H, t,6.5 Hz);

Inter-IIIF:

δ_H 12.62(br,D₂Exchangeable O), 8.06(D,8.0Hz, D₂O interchangeably), 7.25(2H, br dd,7.5,7.5Hz),7.22(2H, br d,7.0Hz),7.18(ddd,7.5,7.5,2.0Hz),4.41(ddd,10.0,8.0,4.5Hz),3.03(15.0,4.5Hz),2.82(dd,15.0,10.0Hz), 2.02(2H, t,6.5Hz),1.37(2H, m),1.30-1.10(12H, m),8.86(3H, t,6.5 Hz).

example 10 preparation of RP001

Inter-IA (10.1mg) of (1: 9) trifluoroacetic acid (TFA)/dichloro-acetic acid (TFA)After stirring a solution of methane (DCM) (500 uL total) at rt for 10 min, acetonitrile (1mL) was added, the solution was evaporated under reduced pressure to a volume of about 200uL and purified by high pressure liquid phase (scheme B2) to give RP001 as a yellow powder (7.7mg) after lyophilization. Positive polarity ESIMS m/z 1648.4(MH)⁺And RP001 (C)₇₄H₁₀₆N₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 11 preparation of RP002

Step 1, preparing RP002-Boc

Inter-IIIA (5.0mg), 1- [ bis (dimethylamino) methylene ] -1H-1,2, 3-triazolo [4,5-b ] pyridinium 3-oxide hexafluorophosphate (4.1mg) and a DMF (150uL) solution of N, N-diisopropylethylamine (20uL) were stirred at room temperature for 10 minutes, and then mixed with a DMF (150uL) solution of Inter-IID (8.2 mg). The mixed solution was further stirred for 15 minutes until the reaction was completed. The product was purified using the high pressure liquid phase (scheme B1) and lyophilized to give RP002-Boc as a yellow powder (4.2 mg).

step 2. preparation of RP002

after stirring a solution of RP002-Boc (4.2mg) in (1: 9) trifluoroacetic acid (TFA)/Dichloromethane (DCM) (250 uL total) at room temperature for 10 minutes, acetonitrile (1.0mL) was added, the solution was evaporated under reduced pressure to a volume of about 100uL and purified with the high pressure liquid phase (scheme B2) to give RP002 as a yellow powder (3.1mg) after lyophilization. Positive polarity ESIMS m/z 1678.6(MH)⁺And RP002 (C)₇₅H₁₀₈N₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 12 preparation of RP003

Step 1, preparing RP 003-Boc.

A solution of Inter-IIIA (5.3mg), HATU (4.5mg) and N, N-diisopropylethylamine (Hunig's base, 20uL) in DMF (150uL) was stirred at room temperature for 10 minutes and then mixed with a solution of Inter-IIE (8.0mg) in DMF (150 uL). The mixed solution was further stirred for 15 minutes until the reaction was completed. The product was purified using the high pressure liquid phase (scheme B1) to give RP003-Boc as a yellow powder (4.8mg) after lyophilization.

Step 2 preparation of RP003

After stirring a solution of RP003-Boc (4.7mg) in (1: 9) TFA/DCM (250 uL total) at room temperature for 10 min, acetonitrile (1.0mL) was added, the solution was evaporated under reduced pressure to a volume of about 100uL and purified using the high pressure liquid phase (scheme B2) to give RP003 as a yellow powder (3.7mg) after lyophilization. Positive polarity ESIMS m/z 1756.4(MH)⁺And RP003 (C)₇₅H₁₀₇BrN₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 13 preparation of RP004

Step 1 preparation of RP004-Boc

A solution of Inter-IIIB (5.0mg), HATU (4.2mg) and N, N-diisopropylethylamine (Hunig's base, 20uL) in DMF (150uL) was stirred at room temperature for 10 minutes and then mixed with a solution of Inter-IID (8.0mg) in DMF (150 uL). The mixed solution was further stirred for 15 minutes until the reaction was completed. The product was purified using the high pressure liquid phase (scheme B1) and lyophilized to give RP004-Boc as a yellow powder (4.9 mg).

Step 2. preparation of RP004

After stirring RP004-Boc (3.9mg) in (1: 9) TFA/DCM (250 uL total) at room temperature for 10 min, acetonitrile (1.0mL) was added, the solution was evaporated under reduced pressure to a volume of about 100uL and purified with the high pressure liquid phase (scheme B2) to give RP004 as a yellow powder (2.9mg) after lyophilization. Positive ESIMS, m/z 1666.5(MH) +, and RP004 (C)₇₄H₁₀₅N₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

example 14 preparation of RP005

Except for Inter-Ithis example is similar to that described in example 12 except that ID is replaced by Inter-IIA. Thus, after coupling Inter-IIIB (5.0mg) to Inter-IIA (7.1mg) and removal of the protective Boc group, RP005 was obtained as a yellow powder (2.8 mg). Positive polarity ESIMS m/z 1734.3(MH)⁺And RP005 (C)₇₄H₁₀₃C_l2FN₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 15 preparation of RP006

This example is similar to that described in example 12, except that Inter-IID is replaced with Inter-IIE. Thus, after coupling Inter-IIIB (5.2mg) with Inter-IIE (8.0mg) and deprotecting the protective Boc group, RP006 was obtained as a yellow powder (3.8 mg). Positive polarity ESIMS m/z 1744.4(MH)⁺and RP006 (C)₇₄H₁₀₄BrFN₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 16 preparation of RP007

This example is similar to that described in example 12, except that Inter-IIIB is replaced with Inter-IIIC. Thus, after coupling Inter-IIIC (5.0mg) with Inter-IID (8.1mg), the protective Boc group was removed to give RP007 as a yellow powder (3.2 mg). Positive ESIMS, m/z 1662.6(MH) +, with RP007 (C)₇₅H₁₀₈N₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 17 preparation of RP008

This example is similar to that described in example 15, except that Inter-IID is replaced with Inter-IIE. Thus, after coupling Inter-IIIC (6.0mg) with Inter-IIE (7.4mg), the protective Boc group was removed to giveRP008 as a yellow powder (4.4 mg). Positive polarity ESIMS m/z 1740.4(MH)⁺And RP008 (C)₇₅H₁₀₇BrN₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 18 preparation of RP009

This example is similar to that described in example 12, except that Inter-IIIB is replaced with Inter-IIID. Thus, after coupling Inter-IIID (5.0mg) with Inter-IID (8.6mg), the protective Boc group was removed to give RP009 as a yellow powder (3.0 mg). Positive polarity ESIMS m/z 1662.5(MH)⁺And RP009 (C)₇₅H₁₀₈N₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 19 preparation of RP010

This example is similar to that described in example 17, except that Inter-IID is replaced with Inter-IIA. Thus, after coupling Inter-IIID (5.0mg) to Inter-IIA (8.1mg), the protective Boc group was removed to give RP010 as a yellow powder (3.1 mg). Positive polarity ESIMS m/z 1730.4(MH)⁺And RP010 (C)₇₅H₁₀₆C_l2N₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 20 preparation of RP011

This example is similar to that described in example 12, except that Inter-IIIB is replaced with Inter-IIIE. Thus, after coupling Inter-IIIE (5.2mg) with Inter-IID (8.4mg), the protective Boc group was removed to give RP011 as a yellow powder (3.2 mg). Positive polarity ESIMS m/z 1662.5(MH)⁺And RP011 (C)₇₅H₁₀₈N₁₇O₂₆) Theoretical mass ofAnd (5) consistent (scheme A2).

Example 21 preparation of RP012

This example is similar to that described in example 19, except that Inter-IID is replaced with Inter-IIA. Thus, after coupling Inter-IIIE (5.2mg) with Inter-IIA (8.0mg), the protective Boc group was removed to give RP012 as a yellow powder (3.8 mg). Positive polarity ESIMS m/z 1730.4(MH)⁺And RP012 (C)₇₅H₁₀₆C_l2N₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 22 preparation of RP013

This example is similar to that described in example 19, except that Inter-IID is replaced with Inter-IIE. Thus, after coupling Inter-IIIE (10.4mg) with Inter-IIE (14.0mg), the protective Boc group was removed to give RP013 as a yellow powder (6.7 mg). Positive polarity ESIMS m/z 1740.4(MH)⁺And RP013 (C)₇₅H₁₀₇BrN₁₇O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 23 preparation of RP014

This example is similar to that described in example 19, except that Inter-IIIE is replaced with Inter-IIIF. Thus, Inter-IIIF (10.0mg) was coupled to Inter-IID (8.9mg) and the protective Boc group was removed to give RP014 as a yellow powder (3.9 mg). Positive polarity ESIMS m/z 1609.4(MH)⁺And RP014 (C)₇₂H₁₀₅N₁₆O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 24 preparation of RP015

This example is similar to that described in example 22, except that Inter-IID is replaced with Inter-IIA. Thus, after coupling Inter-IIIF (5.9mg) to Inter-IIA (8.4mg), the protective Boc group was removed to give RP015 as a yellow powder (3.4 mg). Positive polarity ESIMS m/z 1677.3(MH)⁺And RP015 (C)₇₂H₁₀₃C_l2N₁₆O₂₆) Consistent with the theoretical quality of (protocol a 2).

Example 25 preparation of RP016

Step 1, preparing RP016-Boc 016

to a solution of 3H- [1,2,3] triazolo [4,5-b ] pyridin-3-yldecanoate (3,10.1mg) and Inter-IID (5.2mg) in DMF (200. mu.L) was added triethylamine (20. mu.L), and the reaction mixture was stirred at room temperature for 15 minutes until the reaction was complete. The product RP016-Boc was purified by HPLC (scheme B1) and lyophilized as a yellow powder (3.8 mg).

Step 2. preparation of RP016

After stirring RP016-Boc (3.5mg) in (1: 9) TFA/DCM solution (250 uL total) at room temperature for 10 min, acetonitrile (1.0mL) was added, the solution was evaporated under reduced pressure to a volume of about 100uL and purified using the high pressure liquid phase (scheme B2) to afford RP016 as a yellow powder (3.0mg) after lyophilization. Positive polarity ESIMS m/z 1462.4(MH)⁺And RP016 (C)₆₃H₉₆N₁₅O₂₅) Consistent with the theoretical quality of (protocol a 2).

Example 26 preparation of RP017

This example is similar to that described in example 24, except that Inter-IID is replaced with Inter-IIA. Thus, the reaction is carried out on 3H- [1,2,3]Triazolo [4,5-b]After coupling of pyridin-3-yldecanoate (3,10.5mg) with Inter-IIA (5.5mg), the protective Boc group was removed to give RP017,As a yellow powder (3.7 mg). Positive polarity ESIMS m/z 1530.3(MH)⁺and RP017 (C)₆₃H₉₄C_l2N₁₅O₂₅) Consistent with the theoretical quality of (protocol a 2).

Example 27 preparation of RP018

This example is similar to that described in example 13, except that the Inter-IIA and Hunig bases are replaced with Inter-IIB and 2,4, 6-Trimethylpyridine (TMP), respectively. Thus, after coupling Inter-IIIB (5.5mg) with Inter-IIB (10.1mg) in the presence of HATU and TMP, the protective Boc group was removed to give RP018 as a yellow powder (4.0 mg). Negative ESIMS M/z 858.8(M-2H)^2-And RP018 (C)₇₃H₁₀₀C_l2FN₁₇O₂₆) The theoretical values of (scheme A1-Neg) are consistent.

Example 28 preparation of RP019

This example is similar to that described in example 20, except that the Inter-IIA and Hunig bases are replaced with Inter-IIB and 2,4, 6-Trimethylpyridine (TMP), respectively. Thus, after coupling Inter-IIIE (5.2mg) with Inter-IIB (10.0mg) in the presence of HATU and TMP, the protective Boc group was removed to give RP019 as a yellow powder (3.5 mg). Negative ESIMS M/z 856.8(M-2H)^2-and RP019 (C)₇₄H₁₀₃C_l2N₁₇O₂₆) Of (M-2H)^2-The theoretical values are consistent (scheme A1-Neg).

Example 29 preparation of RP020

This example is similar to that described in example 26, except that Inter-IIB is replaced with Inter-IIC. Thus, Inter-IIIB (5.3mg) was coupled with Inter-IIC (10.0mg) in the presence of HATU and TMPAfter synthesis, the protective Boc group was removed to give RP020 as a yellow powder (5.2 mg). Negative ESIMS M/z 872.8(M-2H)^2-With RP020 (C)₇₅H₁₀₄C_l2FN₁₇O₂₆) The theoretical values of (case A1-Neg) are identical.

Example 30 preparation of RP021

This example is similar to that described in example 27, except that Inter-IIB is replaced with Inter-IIC. Thus, after coupling Inter-IIIE (5.2mg) with Inter-IIC (9.8mg), the protective Boc group was removed to give RP021 as a yellow powder (4.2 mg). Negative ESIMS M/z 870.8(M-2H)^2-With RP021 (C)₇₆H₁₀₇C_l2N₁₇O₂₆) The theoretical values of (case A1-Neg) are identical.

Example 31 preparation of RP022

This example is similar to that described in example 27, except that Inter-IIIE is replaced with Inter-IIIA. Thus, after coupling Inter-IIIA (3.9mg) with Inter-IIC (10.2mg), the protective Boc group was removed to give RP022 as a yellow powder (5.9 mg). Negative ESIMS M/z 878.8(M-2H)^2-And RP022 (C)₇₆H₁₀₇C_l2N₁₇O₂₇) The theoretical values of (case A1-Neg) are identical.

Examples 32 preparation of RP023 and RP024

A solution of RP001(12.2mg), acetic acid (10. mu.L) and tert-butyl (2-oxoethyl) carbamate (21.0mg) in methanol (300. mu.L) was stirred for 5 minutes and then mixed with a methanol (150. mu.L) solution of sodium cyanoborohydride (12.5mg), the resulting mixed solution was stirred at 0 ℃ for another 30 minutes, and the reaction product was purified byPurification of preparative high pressure liquid phase (scheme B1) yielded RP023-Boc (4.6mg) and RP 024-bis-Boc (6.5 mg). The two products were treated with 10% TFA in DCM for 15min and then purified by HPLC (scheme B2) to give RP023(2.6mg) and RP024(3.7 mg). Negative ESIMS of RP 023: m/z844.3(M-2H)^2-，C₇₆H₁₁₀N₁₈O₂₆Of (M-2H)^2-Theoretical value, 844.38 (protocol A1-Neg); negative ESIMS of RP 024: m/z 865.9(M-2H)^2-，C₇₈H₁₁₅N₁₉O₂₆Of (M-2H)^2-Theoretical value, 865.91 (scheme A1-Neg).

Data of pharmaceutical experiment

1) In vitro bacteriostasis evaluation method

the Minimum Inhibitory Concentration (MIC), i.e., the lowest concentration of antibiotic that inhibits the growth of the tested organism, was determined by broth microdilution, as recommended by the national committee for clinical laboratory standards. The present invention uses Muller-Hinton broth (MHB) supplemented with calcium (25mg/L) (see Balouri, M.; Sadiki, M.; Ibnsouda, S.K.; Methods for In visual evaluation of antimicrobial activity: review. journal of pharmaceutical Analysis,2016,6(2), 71-79; CLSI, Methods for diagnostic evaluation of antimicrobial activity Tests for bacterial fat soil aerobic, Approved Standard,9th Ed, CLSI docu M07-A9). Approximately 50uL of bacterial (MRSA or MSSA) cell suspension (1.0X 10) was seeded into each well (96 microwell plates) containing 50uL of drug solution⁶mL) and incubated at 37. + -. 1 ℃ for 18 hours. After incubation, bacterial growth in each well of a 96-well plate was measured calorimetrically at 630nm using a Biotek microtiter plate reader. Bacterial Growth Inhibition (GI) is expressed as a percentage relative to the negative control.

2) Testing

Test A

Bacteria:

Methicillin-resistant Staphylococcus aureus (MRSA, ATCC33591)

Methicillin-sensitive Staphylococcus aureus (MSSA, ATCC6538)

Drug concentration (μ M):

0.039,0.078,0.156,0.313,0.625,1.25,2.50,5.0,10.

The test results are shown in Table 2.

Test B

Bacteria:

methicillin-resistant Staphylococcus aureus (MRSA, PBR Lab Culture #1152)

Methicillin-sensitive Staphylococcus aureus (MSSA, ATCC6538)

Drug concentration (μ M):

0.005,0.020,0.078,0.312,1.250,5.00,20.0.

The test results are shown in Table 3

Test C

Bacteria:

Vancomycin-resistant enterococcus faecalis (VRE, ATCC 700221);

Vancomycin-resistant enterococcus faecalis (VRE, ATCC 51299);

Vancomycin-sensitive Enterococci faecis (VSE, ATCC 29212);

Vancomycin-sensitive Enterococci hirae (VSE, ATCC 1056).

Drug concentration (μ M):

0.156,0.313,0.625,1.250,2.50,5.00,10.0.

The test results are shown in Table 4

As shown in tables 1,2, and 3, compounds RP005 and RP012 were approximately ten-fold more active against methicillin-resistant staphylococcus aureus (MRSA) than daptomycin. RP005 and RP012 also simultaneously showed ten-fold greater activity against vancomycin-resistant enterococci (VRE) than daptomycin. These compounds are useful for treating infections caused by gram-positive bacteria, particularly drug-resistant bacteria.

The invention is not to be limited in scope by the specific embodiments described above. Indeed, various modifications and adaptations thereof will become apparent to those skilled in the art of pharmaceutical chemistry in view of the foregoing description. Therefore, equivalent alterations and modifications are intended to be included within the spirit of this patent.

Claims

1. A novel antibacterial lipopeptide compound and its medicinal salt, characterized by the following structural formula:

Wherein,

R₁、R_1aand R₆each independently is hydrogen, alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl, acyl, OH, OR, NHR, OR NR₂r is selected from C₁–C₆Alkyl, aryl, heteroaryl, and heteroaryl,C₂–C₆Alkenyl radical, C₂–C₆Alkynyl, cycloalkyl, cycloalkenyl, aryl or heteroaryl;

2. A novel antibacterial lipopeptide compound and its medicinal salt, characterized by the following structural formula:

R₁、R_1aat least one group is not a hydrogen group;

3. A novel antibacterial lipopeptide compound and its medicinal salt, characterized by the following structural formula:

4. A compound of any one of the following formulae RP002 to RP 022:

5. A pharmaceutical composition comprising a compound according to any one of claims 1 to 4, a pharmaceutically acceptable salt thereof and one or more pharmaceutically acceptable excipients.

6. Use of a compound according to any one of claims 1 to 4 for the manufacture of a medicament for combating bacterial infections.

7. A compound of formula (Inter-II) having the formula:

Wherein:

R₁、R_1aEach independently is hydrogen, alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl, acyl, OH, OR, NHR, OR NR₂r is selected from C₁–C₆Alkyl radical, C₂–C₆Alkenyl radical, C₂–C₆Alkynyl, cycloalkyl, cycloalkenyl, aryl or heteroaryl;

R₂、R₃、R₄、R₅Each independently is hydrogen, alkyl, halo, alkenyl, cycloalkyl, cycloalkenyl, alkynyl, aryl, heteroaryl, cyano, isocyano, thiocyano, isothiocyanato, phospho, phosphoryl, sulfate, sulfoxide, sulfonyl, formyl, acyl, amino, imino, amide, acyloxy, thiocarbonyl, alkoxycarbonyl, carboxyl, carboxyamino, hydroxyl, nitro, or the likeRadical, nitroso radical, mercapto radical, alkoxy radical, acyloxy radical, OC-ORa, OC-OORa, OC-ONHRa, OC-ON (Ra)₂NHRa or N (Ra)₂(ii) a Wherein Ra may be C₁–C₆Alkyl radical, C₂–C₆Alkenyl radical, C₂–C₆alkynyl, cycloalkyl, cycloalkenyl, aryl or heteroaryl;

8. Use of a compound according to claim 7 for the preparation of a lipopeptide having antibacterial activity.