Cupressus dupreziana

An examination of the minor constituents of Cupressus dupreziana has resulted in the isolation of the three alaskane-type sesquiterpenoids (180)—(182) together with the two 1,7-diepi-cedrane derivatives (183) and (184). In view of the importance of absolute stereochemistry in these and related compounds it is regrettable that the [a]o value of only one of them (183) is quoted. Indeed this is all the more surprising when the comparison of [a]o values has played an important role in the proposals of the same authors to account for the distribution and biogenesis of acorane, alaskane, cedrane, 1,7-diepi-cedrane,... 

Piovetti L, Combaut G, Diara A 1980 Monoterpenes and oxygenated sesquiterpenes from Cupressus dupreziana. Phytochemistry 19 2117-2120... 

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