Volatiles from African species of Croton (Euphorbiaceae), including new diterpenes in essential oil from Croton gratissimus.

ABSTRACT: The chemistry of essential oils from the leaves of three African species of Croton (C. gratissimus, C. pseudopulchellus and C. sylvaticus) is comprehensively characterised. Two new volatile diterpenes were isolated from C. gratissimus and the structures assigned using 1D and 2D NMR. One is a furanyl-halimane methyl ester (1) assigned as 12-β-furanyl-halima-5,9-dien-4-methylcarboxylate (gratissihalimanoic ester); the other is an abietane ketone (2) assigned as ent-abiet-8(14), 13(15)-dien-3-one, which we have named gratissimone. High relative abundance of diterpenes in a hydrodistilled essential oil is rare and may be considered an interesting discovery. Known non-volatile diterpenes were also isolated, which were assigned as crotohalimaneic acid (3) and hardwickiic acid (4). All diterpenes

SUBMITTER: Sadgrove NJ 

PROVIDER: S-EPMC6820369 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature