title: The succulent Euphorbias of Nigeria. II. aliphatic diterpene esters of the latices of E. poisonii Pax. and E. unispina N.E. Br.
abstract: Methanol-preserved latices of E. poisonii and E. unispina were examined for irritant principles. Six esters of the parent diterpene 12-deoxyphorbol were identified by spectroscopic and chemical methods. Three were the aliphatic esters 12-deoxyphorbol-13-(2-methyl-butyrate), 12-deoxyphorbol-13-angelate and 12-deoxyphorbol-13-isobutyrate, and a further three compounds were the 20-acetyl equivalents. Isobutyrate esters were absent from the latex of E. unispina, an observation of possible value in the identification of these two similar species.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D003877:Dermatitis, Contact / Q000209:etiology; D010703:Phorbol Esters / Q000302:isolation & purification; D010704:Phorbols / Q000302:isolation & purification; D010939:Plant Poisoning; D012408:Rubber
chemical_list: D010703:Phorbol Esters; D010704:Phorbols; D012408:Rubber