34695-32-4Relevant articles and documents
Control of β-Branching in Kalimantacin Biosynthesis: Application of 13C NMR to Polyketide Programming
Walker, Paul D.,Williams, Christopher,Weir, Angus N. M.,Wang, Luoyi,Crosby, John,Race, Paul R.,Simpson, Thomas J.,Willis, Christine L.,Crump, Matthew P.
supporting information, p. 12446 - 12450 (2019/08/16)
The presence of β-branches in the structure of polyketides that possess potent biological activity underpins the widespread importance of this structural feature. Kalimantacin is a polyketide antibiotic with selective activity against staphylococci, and its biosynthesis involves the unprecedented incorporation of three different and sequential β-branching modifications. We use purified single and multi-domain enzyme components of the kalimantacin biosynthetic machinery to address in vitro how the pattern of β-branching in kalimantacin is controlled. Robust discrimination of enzyme products required the development of a generalisable assay that takes advantage of 13C NMR of a single 13C label incorporated into key biosynthetic mimics combined with favourable dynamic properties of an acyl carrier protein. We report a previously unassigned modular enoyl-CoA hydratase (mECH) domain and the assembly of enzyme constructs and cascades that are able to generate each specific β-branch.
Studies on a Synthesis of (RS)-Mevalonic Acid Lactone
Bardshiri, Esfandiar,Simpson, Thomas J.,Scott, A. Ian,Shishido, Kozo
, p. 1765 - 1767 (2007/10/02)
Full details of a high yielding synthesis of mevalonic acid lactone (1) which is of particular value in the preparation of 3- and/or 3'-labelled compounds are described.The key step, conversion of 3-hydroxy-3-methylpentane-1,5-dioic acid (3) into 3-hydroxy-3-methylpentane-1,5-dioic anhydride (4) using acetic anhydride, has been fully investigated, and an additional method using acetyl chloride and triethylamine is described.
Macrocyclic Pyrrolizidine Alkaloids. Synthesis and Stereochemistry of (+)-Dicrotaline (13β-Hydroxy-13α-methyl-1,2-didehydrocrotalanine) and (+)-13-epi-Dicrotaline
Brown, Kenneth,Devlin, J. Alastair,Robins, David J.
, p. 1819 - 1824 (2007/10/02)
Treatment of (+)-retronecine (1) with the trimethylsilyl ether of 3-hydroxy-3-methylglutaric anhydride gave a mixture of the 7- and 9-monoesters of (+)-retronecine (1).Lactonisation of this mixture was achieved using the corresponding pyridine-2-thiol esters to give (+)-dicrotaline (13β-hydroxy-13α-methyl-1,2-didehydrocrotalanine) (2) and (+)-13-epi-dicrotaline (3).The absolute configuration at C-13 in both compounds was established by a sequence of selective reactions on each epimer to yield optically active mevalonolactone.
