928-30-3

Upstream product

• 53353-01-8 (S)-1-bromo-4-methylhexane 
• 996-82-7 sodium diethylmalonate 
• 110453-78-6 (S)-(+)-6-methyl-1-octanol 
• 1730-89-8 (S)-4-methylhexanoic acid 
• 3878-55-5 methyl hydrogen succinate 
• 105-53-3 diethyl malonate 
• 145142-82-1 leustroducsin B 
• 50837-11-1 (S)-1-bromo-5-methylheptane 
• 124-38-9 carbon dioxide 
• 467234-66-8 (S)-6-Methyl-octanoic acid (1S,3R)-3-[(1Z,3Z,9E)-(5R,7R,8R)-8-(2-allyloxycarbonylamino-ethyl)-10-((2S,3S)-3-ethyl-6-oxo-3,6-dihydro-2H-pyran-2-yl)-5,7,8-trihydroxy-deca-1,3,9-trienyl]-cyclohexyl ester 
• 467234-67-9 (S)-6-Methyl-octanoic acid (1S,3R)-3-[(1Z,3Z,9E)-(5R,7R,8R)-8-(2-allyloxycarbonylamino-ethyl)-10-((2S,3S)-3-ethyl-6-oxo-3,6-dihydro-2H-pyran-2-yl)-5,7-dihydroxy-8-trimethylsilanyloxy-deca-1,3,9-trienyl]-cyclohexyl ester 
• 467234-68-0 (S)-6-Methyl-octanoic acid (1S,3R)-3-[(1Z,3Z,9E)-(5R,7R,8R)-8-(2-allyloxycarbonylamino-ethyl)-5-(2-chloro-acetoxy)-10-((2S,3S)-3-ethyl-6-oxo-3,6-dihydro-2H-pyran-2-yl)-7-hydroxy-8-trimethylsilanyloxy-deca-1,3,9-trienyl]-cyclohexyl ester 
• 1565-80-6 (2S)-2-methyl-1-butanol 
• 534-00-9 (S)-2-methylbutyl bromide 

Downstream Products

• 5746-59-8 (S)-(+)-14-methylhexadecanoic acid 
• 467234-65-7 (S)-6-Methyl-octanoic acid (1S,3R)-3-((1Z,3Z)-4-{(4R,6R)-6-[(E)-(R)-1-(2-allyloxycarbonylamino-ethyl)-3-((2S,3S)-3-ethyl-6-oxo-3,6-dihydro-2H-pyran-2-yl)-1-hydroxy-allyl]-2,2-dimethyl-[1,3]dioxan-4-yl}-buta-1,3-dienyl)-cyclohexyl ester 
• 120581-48-8 N-[(R)-4-benzyloxycarbonylamino-2-((S)-6-methyl-octanoylamino)-butyryl]-L_s-threonine 
• 1369415-68-8 methyl 6-((1S,2R,6S)-2-((S)-4-benzyl-2-oxooxazolidine-3-carbonyl)-1-hydroxy-6-methyloctyl)phenazine-1-carboxylate 
• 1369415-67-7 (S)-4-benzyl-3-((S)-6-methyloctanoyl)oxazolidin-2-one 

Relevant academic research and scientific papers

Enantiomeric separation of carboxylic acids having chiral centers remote from the carboxyl group by labelling with a chiral fluorescent derivatization reagent

Enantiomeric separations of 2-, 3-, 4-, 5- and 6-methyl fatty acids and 3-, 4- and 5-hydroxy fatty acids derivatized with (S) -(+)-2-(anthracene-2,3-dicarboximido)-1 propyl trifluoromethanesulfonate are described. Although there are 4-8 bond distances between the chiral centers of these diastereomeric derivatives, they are separated on HPLC and detected at fmol levels.

PEPTIDE ANTIBIOTICS

There is provided a range of novel compounds. These novel compounds may demonstrate a broad spectrum antibacterial and antifungal activity. These compounds may be active against the emerging polymyxin resistant bacteria. These compounds may also be useful

Synthesis and Bioactivity Investigation of the Individual Components of Cyclic Lipopeptide Antibiotics

In this paper, 26 natural polymyxin components and a new derivative S2 were synthesized, and their differences in efficacy and toxicity have been investigated. Almost all of the synthesized components showed strong activity against both susceptible and resistant strains of E. coli, K. pneumoniae, P. aeruginosa, and A. baumannii. The toxicities were obviously different between the components. Only some of the components were tested for toxicity in vivo. Compounds E2, E2-Val, A2, M2, D2, and S2 showed obviously lower renal cytotoxicity and acute toxicity than polymyxins B and E. The in vivo nephrotoxicity of E2, M2, and S2 was similar to that of polymyxin E. Compound S2, with four positive charges, was especially interesting as it possessed both increased efficacy and decreased toxicity. The SAR and toxicity studies indicated that further structural modification could concentrate on polymyxin S. The results also indicated that S2 could be a new drug candidate.

A Highly Convergent Total Synthesis of Leustroducsin B

Leustroducsin B exhibits a large variety of biological activities and unique structural features. An efficient and highly convergent total synthesis of Leustroducsin B was achieved in 17 longest linear and 39 total steps by disconnecting the molecule into three fragments having similar levels of complexity. These pieces were connected via a highly efficient chelate-controlled addition of a vinyl zincate to an α-hydroxy ketone and a silicon-mediated cross-coupling. The stereochemistry of the central and western fragments was set catalytically in high yields and excellent de by a zinc-ProPhenol-catalyzed aldol reaction and a palladium-catalyzed asymmetric allylic alkylation.

Studies on tridecaptin B1, a lipopeptide with activity against multidrug resistant Gram-negative bacteria

Previously other groups had reported that Paenibacillus polymyxa NRRL B-30507 produces SRCAM 37, a type IIA bacteriocin with antimicrobial activity against Campylobacter jejuni. Genome sequencing and isolation of antimicrobial compounds from this P. polymyxa strain show that the antimicrobial activity is due to polymyxins and tridecaptin B1. The complete structural assignment, synthesis, and antimicrobial profile of tridecaptin B1 is reported, as well as the putative gene cluster responsible for its biosynthesis. This peptide displays strong activity against multidrug resistant Gram-negative bacteria, a finding that is timely to the current problem of antibiotic resistance.

Nocapyrones: α- and γ-pyrones from a marine-derived Nocardiopsis sp

One new α-pyrone (nocapyrone R (1)), and three known γ-pyrones (nocapyrones B, H and L (2-4)) were isolated from the culture extract of a Nocardiopsis strain collected from marine sediment. Structures of these compounds were determined on the basis of spectroscopic data including NMR and MS. γ-Pyrones 2-4 were found to induce adiponectin production in murine ST-13 preadipocyte cells but the α-pyrone 1 had no activity. The absolute configuration of the anteiso-methyl branching in 4 was determined by HPLC comparison of a degraded product of 4 with standard samples as a 2:3 enantiomeric mixture of (R)- and (S)-isomers.

Asymmetric synthesis and absolute configuration of streptophenazine G

The asymmetric synthesis of the antibacterial natural product, streptophenazine G, has been achieved by employing asymmetric alkylation and asymmetric aldol reactions using chiral oxazolidinones as the key steps. The originally proposed structure for streptophenazine G has been revised, and its absolute configuration has been determined to be 1′S,2′R,6′S. The asymmetric total synthesis of 6′-epi-streptophenazine G is also described.

Volatile lactones - (5S,S)-5-methyl-3-(methylalkyl)furan-2(5H)-ones - Identified in the submerged cultivation of Streptomyces avermitilis

Six new compounds have been identified in the volatile fractions produced during the submerged cultivation of Streptomyces avermitilis. By recording the GC/MS, GC/FTIR, CD, 1H and 13C NMR data and by performing chemical degradation experiments, these compounds were determined to be (5S,S)-5-methyl-3-(methylalkyl)furan-2(5H)-ones. Herein, the existence of volatile lactones with an anteiso structure of the side-chain is thus documented for the first time. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.

Chemical transformation of Leustroducsins: Synthesis of Leustroducsin B

Chemical transformation of Leustroducsin H to Leustroducsin B has been successfully accomplished in 11 steps including enzymatic hydrolysis of phosphate ester. The process described here enables to differentiate all hydroxyl groups, amino and phosphate fu

Enatiomeric separation of branched fatty acids after conversion with trans-2-(2,3-Anthracenedicarboximido)cyclohexanol, a highly sensitive chiral fluorescent conversion reagent

(1R,2R)-2-(2,3-Anthracenedicarboximido)cyclohexanol was synthesized as a highly sensitive chiral fluorescent conversion reagent. The diastereomeric derivatives of chiral branched fatty acids that had methyl ethyl chirality from the 2 to 12 position were separated into 2 peaks by reversed-phase HPLC and detected at the 10-15 mole level by fluorometry.