Bacterial infections evading the current antibiotic arsenal warrant new treatment options. The mainstay treatment for Clostridium difficile infections involves administration of the broad-spectrum antibiotic vancomycin, which also depletes the gut microbiome and its natural defenses. This leads to recurrent C. difficile infections in 20-30% of patients. Alternative treatment options are limited, triggering a perpetual cycle of relapse and recovery that may eventually lead to death. Keratinicyclin B represents a glycopeptide antibiotic chemotype with a mechanism of action that is selective for Clostridia. When combined, vancomycin (or other glycopeptide antibiotic) and keratinicyclin B interact synergistically to inhibit the growth of C. difficile at concentrations far lower than their respective minimal inhibitory concentrations. Such a combination therapy could allow for targeted colonization clearance at low antibiotic doses, thereby minimizing toxicity and reducing the likelihood of relapse.

Vancomycin conjugates of Formula I, its stereoisomers, prodrugs, pharmaceutically acceptable salts, and metal coordination complexes thereof is described in the present disclosure. Further, the present disclosure relates to pharmaceutical compositions comprising vancomycin conjugates, its stereoisomers, prodrugs, pharmaceutically 10 acceptable salts, metal coordination complex thereof with one or more other pharmaceutical compositions or an antibiotic. The present disclosure also describes a process of preparing said conjugates, its stereoisomers, prodrugs, pharmaceutically acceptable salts, and metal coordination complex thereof, and pharmaceutical compositions as described above. Furthermore, the present disclosure describes 15 compositions and methods of treating conditions and diseases that are mediated by bacteria

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The present invention discloses glycopeptide compounds having activity of resisting drug-resistant bacteria, conforming to glycopeptide compounds represented by general formula (I), ##STR00001## The present invention also provides a preparation method for and an application of the glycopeptide compounds. Upon testing, compared with a second-generation glycopeptide drug oritavancin, the glycopeptide antibiotic compounds have higher inhibition activity on drug-resistant bacterial strains, especially MRSA or VRE. Further testing shows that most of the glycopeptide compounds have safety higher than that of oritavancin and can be prepared into drugs for treating or preventing diseases caused by various bacterial infections, such as skin and soft tissue infections, meningitis, sepsis, pneumonia, arthritis, peritonitis, bronchitis, and empyema.

Disclosed herein is a rapid genetics-free method for eliciting and detecting cryptic metabolites using an imaging mass spectrometry-based approach. An organism of choice is challenged with elicitors from a small molecule library. The molecules elicited are then imaged by mass spec, which allows for rapid identification of cryptic metabolites. These are then isolated and characterized. Employing the disclosed approach activated production of cryptic glycopeptides from an actinomycete bacterium. The molecules that result, the keratinimicins and keratinicyclins, are metabolites with important structural features. At least two of these, keratinimicins B and C, are highly bioactive against several pathogenic strains. This approach will allow for rapid activation and identification of cryptic metabolites from diverse microorganisms in the future.

Microorganisms are prolific producers of natural products, a group of molecules that make up the majority of drugs approved by the FDA in the past 35 years. After decades of mining, the low-hanging fruit has been picked and so discovery of drug-like molecules from microorganisms has come to a near-halt. The reason for this lack of productivity is that most biosynthetic pathways that give rise to natural products are not active under typical laboratory growth conditions. These so-called ‘cryptic’ or ‘silent’ pathways are a major source of new bioactive molecules and methods that reliably activate them could have a profound impact on drug discovery. Disclosed herein is a rapid genetics-free method for eliciting and detecting cryptic metabolites using an imaging mass spectrometry-based approach. An organism of choice is challenged with elicitors from a small molecule library. The molecules elicited are then imaged by mass spec, which allows for rapid identification of cryptic metabolites. These are then isolated and characterized. Employing the disclosed approach activated production of cryptic glycopeptides from an actinomycete bacterium. The molecules that result, the keratinimicins and keratinicyclins, are metabolites with important structural features. At least two of these, keratinimicins B and C, are highly bioactive against several pathogenic strains. This approach will allow for rapid activation and identification of cryptic metabolites from diverse microorganisms in the future.

A series of vancomycin C-terminus guanidine modifications are disclosed that improve antimicrobial activity, enhance the durability of antimicrobial action against selection or induction of resistance, and provide two synergistic mechanisms of action independent of D-Ala-D-Ala binding that cause inhibition of cell wall biosynthesis, while inducing bacterial cell permeability. A contemplated compound contains two combined peripheral modifications, a (4-chlorobiphenyl)methyl (CBP) and C-terminus guanidine modification, that provide new treatments against not only vancomycin-sensitive, but especially vancomycin-resistant bacteria. The data demonstrate that the synergistic behavior of the peripheral modifications requires the presence of both the CBP and guanidine modifications in a single molecule versus their combined use as an equimolar mixture of singly modified compounds. A prototypical member of the series, G3-CBP-vancomycin (15), exhibits no hemolytic activity, displays no mammalian cell growth inhibition, and possesses improved and especially attractive in vivo pharmacokinetic (PK) properties.

Provided herein are antibacterial compounds, wherein the compounds in some embodiments have broad spectrum bioactivity. In various embodiments, the compounds act by inhibition of bacterial type 1 signal peptidase (SpsB), an essential protein in bacteria. Pharmaceutical compositions and methods for treatment using the compounds described herein are also provided.

The present disclosure provides a compound of Formula I or its stereoisomers, prodrugs and pharmaceutically acceptable salts thereof. The present disclosure also relates to process of preparation of vancomycin-sugar conjugates of Formula I, its stereoisomers, prodrugs, pharmaceutically acceptable salts thereof, and to pharmaceutical compositions containing them. The compounds of the present disclosure are useful in the treatment, prevention or suppression of diseases mediated by microbes.

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The present invention provides a vancomycin derivative, and a preparation method and an application thereof. The vancomycin derivative of the present invention is obtained by introducing a glycerate moiety between a vancomycin derivative and a liposoluble modification group and has reduced liposolubility and improved water solubility, thereby reducing a side effect in the cardiovascular aspect.

Provided herein are lipidated glycopeptide compounds of formula (I); or a pharmaceutically acceptable salt, stereoisomer, solvate, or prodrug thereof. R.sub.1 is a lipid, R.sub.2 is —H or a lipid, and R.sub.3 and R.sub.4 are as defined herein. These compounds have antibiotic activity. Also provided are formulations comprising such compounds; as well as such compounds or formulations for use as a medicament. The compounds and formulations may also be used in the treatment of bacterial infection.

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