Ju. Jeong et Pl. Fuchs, CEPHALOSTATIN CHEMISTRY .6. SYNTHESIS OF THE SOUTH HEXACYCLIC STEROIDUNIT OF CEPHALOSTATIN-7, Tetrahedron letters, 36(14), 1995, pp. 2431-2434
Transformation of alcohol 3 to S-12H, a hexacyclic steroid bearing the
requisite functionality and spiroketal stereochemistry of the symchir
al South portion of cephalostatin 7 (1) is described.