19865-77-1Relevant academic research and scientific papers
Studies on triterpenoids: Conversion of friedelanones into some secofriedelanes
Patra, Amarendra,Chaudhuri, Swapan K.
, p. 376 - 380 (2007/10/02)
Baeyer-Villiger oxidation of friedelin (1), cerin (3), its acetate (4) and canophyllol (7) with m-chloroperbenzoic acid yields friedelolactone (2), 2α-hydroxyfriedelolactone (5), 2α-acetoxyfriedelolactone (6) and apetalactone (8), respectively.However, 3α-hydroxyfriedelan-2-one (12) and its acetate (13) give a 2,3:3,4-disecofriedelane (14) under similar conditions.The formate ester so produced affords a methyl ester (15) upon treatment with diazomethane while basic hydrolysis and acidification leads to a nor-δ-lactone (16).Sodium borohydride reduction of friedelolactone, 2α-hydroxyfriedelolactone and the nor-δ-lactone leads to reductive opening of the lactone ring.CrO3/py oxidation of 3,4-secofriedelan-3,4-diol (17), produced from friedelolactone, yields 3,4-secofriedelan-3-ol-4-one (23).Basic hydrolysis of friedelolactone gives a hydroxy acid (25) which undergoes CrO3/py oxidation to a 4-oxo-compound (28).The latter (28) forms a methyl ester (29) and also undergoes Baeyer-Villiger oxidation to an acetate (30) which on hydrolysis affords another nor-δ-lactone (31).
