229166-07-8Relevant academic research and scientific papers
Studies on the biosynthesis of paraherquamide. Construction of the amino acid framework
Stocking,Sanz-Cervera,Unkefer,Williams
, p. 5303 - 5320 (2007/10/03)
It has been previously established in this laboratory that the β-methyl-β-hydroxyproline moiety of the potent anthelmintic agent paraherquamide A, is biosynthetically derived from L-isoleucine. The downstream events from L-Ile to paraherquamide A have now been investigated. The synthesis of [1-13C]-labeled L-β-methylproline is described by means of a Hoffman-Loeffler-Freytag reaction sequence from [1-13C]-L-Ile. This amino acid is shown to be a direct biosynthetic precursor to paraherquamide A by feeding and incorporation experiments in growing cultures of Penicillium fellutanum. Three tryptophan-containing dipeptides of L-β-methylproline have been constructed: [13C2]-2-(1,1-dimethyl-2-propenyl)-L-tryptophanyl- 3(S)-methyl-L-proline; [13C2]-3(S)-methyl-L-prolyl-2- (1,1-dimethyl-2-propenyl)-L-tryptophan and [13C2]-cyclo-2-(1,1-dimethyl-2-propenyl)-L- tryptophan-3(S)-methyl-L-proline. [α-15N, 1-13C]-2-(1,1-Dimethyl-2-propenyl)-L-tryptophan was also prepared but none of these substances were found to serve as biosynthetic precursors to paraherquamide A.
