199729-60-7

Upstream product

• 1134641-30-7 sanguinamide B 
• 1572176-33-0 stylissamide G 
• 82111-44-2 leucinostatin A 

Relevant academic research and scientific papers

Antibacterial Cyclic Lipopeptide Enamidonins with an Enamide-Linked Acyl Chain from a Streptomyces Species

Three cyclic lipopeptides, including one known (1) and two new (2 and 3) compounds, that possess the rare enamide linkage group were discovered from Streptomyces sp. KCB14A132, an actinobacterium isolated from a soil sample collected from Jeung Island, Korea. The NMR and MS-based characterization showed that they differed in the amino acid residues in the peptide backbone. Application of Marfey's analysis, GITC derivatization, and modified Mosher's method, as well as ECD measurements provided the absolute configurations of enamidonin (1) and those of new compounds enamidonins B and C (2 and 3). The two new enamidonin analogues were shown to exhibit antibacterial activity against Gram-positive bacteria including methicillin-resistant and quinolone-resistant Staphylococcus aureus. Furthermore, evaluation of the extraction conditions and a close inspection of the LC-MS chromatograms revealed that the N,N-acetonide unit of the enamidonin family was formed during the acetone extraction process. The chemically prepared deacetonide derivatives of enamidonins were found to lack antibacterial activity, demonstrating that the dimethylimidazolidinone residue is necessary for antibacterial activity.

Emerimicins V-X, 15-Residue Peptaibols Discovered from anAcremoniumsp. Through Integrated Genomic and Chemical Approaches

Fermentation ofAcremonium tubakiiW. Gams isolated from a soil sample collected from the University of Utah led to the isolation and characterization of six new linear pentadecapeptides, emerimicins V-X (1-6). Peptaibols containing 15-residues are quite rare, with only 22 reported. Genome mining and bioinformatic analysis were used to identify the emerimicin 60 kbpemebiosynthetic cluster harboring a single 16-module hybrid polyketide-nonribosomal peptide synthetase. A detailed bioinformatic investigation of the corresponding 15 adenylation domains, combined with 1D and 2D NMR experiments, LC-MS/MS data, and advanced Marfey’s method, allowed for the elucidation and absolute configuration of all proteinogenic and nonproteinogenic amino acid residues in1-6. As some peptaibols possess cytotoxic activity, a zebrafish embryotoxicity assay was used to evaluate the toxicity of the six emerimicins and showed that emerimicin V (1) and VI (2) exhibit the most potent activity. Additionally, out of the six emerimicins,1displayed modest activity againstEnterococcus faecalis, methicillin-resistant Staphylococcus aureus, and vancomycin-resistantEnterococcus faecium with MIC values of 64, 32, and 64 μg/mL, respectively.

Isolation and structure determination of a new antibacterial peptide pentaminomycin C from Streptomyces cacaoi subsp. cacaoi

A new antibacterial peptide named pentaminomycin C was isolated from an extract of Streptomyces cacaoi subsp. cacaoi NBRC 12748T, along with a known peptide BE-18257A. Pentaminomycin C was determined to be a cyclic pentapeptide containing an un

Fuscasins A-D, Cycloheptapeptides from the Marine Sponge Phakellia fusca

Four new cycloheptapeptides, fuscasins A-D (1-4), were isolated from the marine sponge Phakellia fusca collected from the South China Sea. Their planar structures were fully characterized by spectroscopic methods, and the absolute configurations of amino acid residues were determined using the advanced Marfey's method. Structurally, 1 is a unique cycloheptapeptide with a backbone bearing a pyrrolidine-2,5-dione unit. Among the isolated compounds, 1 exhibited potent growth-inhibitory activity against HepG2 cells with an IC50 value of 4.6 μM, whereas it did not show apparent inhibitory effects against the other five human cancer cell lines, MCF-7, HeLa, NCI-H460, PC9, and SW480. Encouragingly, 1 exhibited no cytotoxicity against nonmalignant cells even with a concentration up to 100 μM. These findings suggest that 1 may display a selective inhibitory effect on the growth of HepG2 cells.

Leucinostatin Y: A Peptaibiotic Produced by the Entomoparasitic Fungus Purpureocillium lilacinum 40-H-28

Leucinostatin Y, a new peptaibiotic, was isolated from the culture broth of the entomoparasitic fungus Purpureocillium lilacinum 40-H-28. The planar structure was elucidated by detailed analysis of its NMR and MS/MS data. The absolute configurations of the amino acids were partially determined by an advanced Marfey's method. The biological activities of leucinostatin Y were assessed using human pancreatic cancer cells, revealing the importance of the C-terminus of leucinostatins for preferential cytotoxicity to cancer cells under glucose-deprived conditions and inhibition of mitochondrial function.

Cyclic Cystine-Bridged Peptides from the Marine Sponge Clathria basilana Induce Apoptosis in Tumor Cells and Depolarize the Bacterial Cytoplasmic Membrane

Investigation of the sponge Clathria basilana collected in Indonesia afforded five new peptides, including microcionamides C (1) and D (2), gombamides B (4), C (5), and D (6), and an unusual amide, (E)-2-amino-3-methyl-N-styrylbutanamide (7), along with 11 known compounds, among them microcionamide A (3). The structures of the new compounds were elucidated by one- and two-dimensional NMR spectroscopy as well as by high-resolution mass spectrometry. The absolute configurations of the constituent amino acid residues in 1-7 were determined by Marfey's analysis. Microcionamides A, C, and D (1-3) showed in vitro cytotoxicity against lymphoma (Ramos) and leukemia cell lines (HL-60, Nomo-1, Jurkat J16), as well as against a human ovarian carcinoma cell line (A2780) with IC50 values ranging from 0.45 to 28 μM. Mechanistic studies showed that compounds 1-3 rapidly induce apoptotic cell death in Jurkat J16 and Ramos cells and that 1 and 2 potently block autophagy upon starvation conditions, thereby impairing pro-survival signaling of cancer cells. In addition, microcionamides C and A (1 and 3) inhibited bacterial growth of Staphylococcus aureus and Enterococcus faecium with minimal inhibitory concentrations between 6.2 and 12 μM. Mechanistic studies indicate dissipation of the bacterial membrane potential.

Antimycobacterial Rufomycin Analogues from Streptomyces atratus Strain MJM3502

This study represents a systematic chemical and biological study of the rufomycin (RUF) class of cyclic heptapeptides, which our anti-TB drug discovery efforts have identified as potentially promising anti-TB agents that newly target the caseinolytic protein C1, ClpC1. Eight new RUF analogues, rufomycins NBZ1-NBZ8 (1-8), as well as five known peptides (9-13) were isolated and characterized from the Streptomyces atratus strain MJM3502. Advanced Marfey's and X-ray crystallographic analysis led to the assignment of the absolute configuration of the RUFs. Several isolates exhibited potent activity against both pathogens M. tuberculosis H37Rv and M. abscessus, paired with favorable selectivity (selectivity index >60), which collectively underscores the promise of the rufomycins as potential anti-TB drug leads.

Structure elucidation at the nanomole scale. 1. Trisoxazole macrolides and thiazole-containing cyclic peptides from the nudibranch Hexabranchus sanguineus

A single specimen of Hexabranchus sanguineus, a nudibranch from the Indo-Pacific that is known to sequester kabiramides B and C and other trisoxazole macrolides, yielded new kabiramide analogues, 9-desmethylkbiramide B and 33-methyltetrahydrohalichondrami

Argicyclamides A-C Unveil Enzymatic Basis for Guanidine Bis-prenylation

Guanidine prenylation is an outstanding modification in alkaloid and peptide biosynthesis, but its enzymatic basis has remained elusive. We report the isolation of argicyclamides, a new class of cyanobactins with unique mono- and bis-prenylations on guanidine moieties, from Microcystis aeruginosa NIES-88. The genetic basis of argicyclamide biosynthesis was established by the heterologous expression and in vitro characterization of biosynthetic enzymes including AgcF, a new guanidine prenyltransferase. This study provides important insight into the biosynthesis of prenylated guanidines and offers a new toolkit for peptide modification.

Melicopteline A-E, Unusual Cyclopeptide Alkaloids with Antiviral Activity against Influenza A Virus from Melicope pteleifolia

In the search for antiviral cyclopeptides against influenza A virus, five unprecedented Caryophyllaceae-type cyclopeptides (1-5) were isolated from the leaves of Melicope pteleifolia. Their chemical structures and absolute configurations were unambiguousl