Synthesis of medium ring ethers. Part 3. Disproof of the proposed 2,8-disubstituted oxocane structure for gloeosporone. Synthesis of pseudo-gloeosporone
作者:Robert W. Carling、J. Stephen Clark、Andrew B. Holmes、Dirk Sartor
DOI:10.1039/p19920000095
日期:——
Synthesis of the cis- and trans-2,8-disubstituted oxocane derivatives 2 and 3 (carrying the unusual gamma,delta-diketohexanecarboxylic acid side chain) by ozonolysis of the alkynes 14 and 18 (prepared respectively from the alcohols 11 and 15) demonstrated unequivocally that neither of these compounds nor their hydroxy-gamma-lactone ring (lactol) tautomers 1 corresponded to the naturally occurring fungal self germination inhibitor gloeosporone. A study of 4,5-dioxohexanoic itself 9 revealed a remarkably low tendency to exist as its hydroxy-gamma-lactone (lactol) tautomer 10.
Structural and synthetic studies of the spore germination autoinhibitor, gloeosporone
作者:Stuart L. Schreiber、Sarah E. Kelly、John A. Porco、Tarek. Sammakia、Edward M. Suh
DOI:10.1021/ja00226a041
日期:1988.8
conidia of Colletotrichum gloeosporioides. The structure initially proposed by Meyer et al. contained an unusual oxOcane ring system (la). A stereoselectivesynthesis of one of the two possible stereoisomeric forms of the oxocane structure that cast doubt on the structural proposal is described. Reinvestigation of the natural product resulted in the formulation of a structure that contains a 14-membered macrolide