Search

trans-[1-14C]Dehydromaticaria ester (CH3·[CC]3·CH[graphic omitted]CH·CO2Me) is specifically converted in cultures of (i)Tricholoma grammopodium(Bull.) Fr. into dehydromatricarianol (CH3·[CC]3·CH[graphic omitted]CH·CH2·OH), (ii)T. paneolum Fr. to 10-hydroxydehydromatricaria acid (HO·CH2·[CC]3·CH[graphic omitted]CH·CO2H), (iii)Merulius lacrymans(Jacq.) Fr. to the dicarboxylic acid (HO2C·[CC]3·[CH2]2·CO2H) and (iv)Coprinus quadrifidus Pk. to the C9-triol {HCC·[CC]2·CH(OH)·CH(OH)·CH2OH}. The incorporations (3·4–46%) indicate that the above ester or a close relative is a precursor of the fungal C10(and C9) polyacetylenes.

Labelled diethyl malonate, methyl oleate, methyl linoleate, and methyl crepenynate (CH3·[CH2]4·CC·CH2·CHCH·[CH2]7·CO2Me) were all incorporated into the triol CH3·CH2·CH(OH)·[CC]2·CH(OH)·CH2·OH by cultures of the fungus in the expected manner. Specifically labelled (14C and 3H) lachnophyllum ester (CH3·CH2·CH2·[CC]2·CHCH·CO2Me) has been synthesised and also shown to be a precursor of the triol.A new metabolite, CH3[graphic omitted]CH·[CC]2·CH2·CH2·OH, has been isolated.

The structure of the polyacetylenic keto-aldehyde {H2CCH·CO·[CC]2·CH2·CH[graphic omitted]CH·[CH2]7·CHO} has been determined. It is the first C18 polyacetylene to be isolated from a plant (Pastinaca sativa L.) of the main polyacetylene-producing families. Its occurrence almost certainly establishes the derivation of the C17 falcarinone and related compounds and is in harmony with Bu'Lock's hypothesis for the biogenesis of the natural acetylenes.

The new polyacetylenes HO2C·[CC]3·CH2·CH2·OH, cis- and trans-Me[CC]2·CHCH·CH2·CH2·OH, [Me[CC]3·CH2·CH2·OH, and (-)-Me[CC]3·CH(OH)·CH2·OH, as well as the known diol HO·CH2·CH2·[CC]2·CH2·CH2·OH, also new as a fungal metabolite, have been detected in extracts from the culture fluids of C. peronata and also synthesised.

Polyacetylenes occur widely in the plant family Campanulaceae. From Campanula glomerata L. 9-(tetrahydropyran-2-yl)-nona-trans,trans-2,8-diene-4,6-diyn-1-ol and 9-(tetrahydropyran-2-yl)-non-trans-8-ene-4,6-diyn-1-ol have been isolated and their structures confirmed by synthesis.

Biosynthetic experiments with a number of differently 14C-labelled hypothetical precursors have shown that cellocidin (acetylenedicarboxamide) is an offshoot of the Krebs cycle and arises in Streptomyces SF-536 cultures directly from carbon atoms 2–5 of 2-oxoglutarate.

Both [1-14C]- and [2-14C]-acetate have been fed to Dahlia plants and the radioactive benzenoid polyacetylene Ph·[CC]2·CHCHMe isolated. Its selective degradation revealed a uniform labelling of alternate carbon atoms in the side-chain with the terminal methyl group derived from the methyl group of acetate and a benzene ring activity which, although not located, also agrees with an alternating labelling of its carbon atoms.Chodkiewicz coupling has been used to improve the syntheses of the cis- and trans-isomers of the phenyl-heptenediyne and osmium tetroxide oxidation to convert them into the erythro- and threo-isomers of the diol Ph·[CC]2·CH(OH)·CHMe·OH.

Three new C14 polyacetylenes, the epoxy-alcohol (R = CH2·OH) and aldehyde (R = CHO) RCHCH·[CC]2·CH([graphic omitted]H·[graphic omitted], and the triol, HO·CH2·CHCH·[CC]2·CH(OH)·CH(OH)·[graphic omitted], as well as the known alcohol, HO·CH2·CHCH·[CC]2·CHCH·[graphic omitted] have been detected in extracts from Trachelium caeruleum L. A partial structure for another constituent, a C14 enediynene diol, is proposed. The two epoxides and the triol have been synthesised and their stereochemistry partly elucidated.

Specifically labelled methyl crepenynate and oleate have been synthesised from the C9 phosphoranes, Me[CH2]4·CC·CH2·CHPPh3 and Me[CH2]7·CHPPh3, respectively, and the C9 aldehyde ester, OCH·[CH2]7·CO2Me; methyl linoleate has been obtained by partial hydrogenation of the crepenynate. Carbon-14 was introduced into the C18 esters via the [9-14C]- and [1,9-14C]-aldehyde esters, and tritium via a reaction of the phosphoranes with tritiated methanol. Several routes to the labelled C9 aldehyde ester are described.

3-Oxosteriods laking a 17-substituent are hydroxylated in the 16-poistion by Rhizopus nigricans.

The new acetylenic nitrile NC·CC·CH[graphic omitted] has been isolated from the culture fluids of L. glaucocana. It is accompanied by four known acetylenic acids already found to be produced by L. diemii.

The hydrocarbon trans-Ph·[CC]2·CHCHMe (tritium-labelled in the benzene ring) was inserted into the tuberous roots of two Dahlia hybrids and found to be converted into the ω-alcohol trans-Ph·[CC]2·CHCH·CH2·OH, the threo-diol Ph·[CC]2·CH(OH)·CHMe·OH, and the threo-triol Ph·[CC]2·CH(OH)·CH(OH)·CH2·OH, but not into the hydrocarbon Ph·[CC]3·Me. The diol and triol had not previously been recognised as natural products.