Showing papers on "Penicillium griseofulvum published in 1981"
TL;DR: In this article, it was shown that tryptophan was incorporated into α-cycopiazonic acid with loss of the 3-pro-S hydrogen atom at the expected C-4 position.
Abstract: Feeding experiments with (3R)- and (3S)-[3-3H] tryptophan have shown that, in Penicillium griseofulvum Dierckx, incorporation of tryptophan into α-cycopiazonic acid (1) proceeds with loss of the 3-pro-S hydrogen atom. [3-2H2]Tryptophan was converted by P. griseofulvum into α-cyclopiazonic acid which was shown by 2H n.m.r. spectroscopy to contain deuterium only at the expected C-4 position. (2RS)-[2-3H,3-14C]Tryptophan was incorporated into α-cyclopiazonic acid (1) with loss of ca. 50% of the tritium. These findings are consistent with cyclisation of β-cyclopiazonic acid (4) to α-cyclopiazonic acid (1)via a 1,4-didehydro-derivative, with C–C bond formation at C-4 occurring from the side of the molecule opposite to that from which proton removal takes place.
18 citations