Krempenes A–D: A Series of Unprecedented Pregnane-Type Steroids from the Marine Soft Coral Cladiella krempfi

✍ Scribed by Xinping Huang; Zhiwei Deng; Xiaobin Zhu; Leen van Ofwegen; Peter Proksch; Wenhan Lin

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: German
• Weight: 76 KB
• Volume: 89
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.200690192

✦ Synopsis

Four new pregnane-type steroids, krempenes A -D (1 -4), were isolated from the marine soft coral Cladiella krempfi. Their structures were elucidated on the basis of 1D-and 2D-NMR analyses, as well as MS experiments. Krempene A (1) contains a very unusual structural motif, with a hexacyclic oxadithiino unit fused to the steroidal ring A. Krempene B ( 2) is a 19-norpregnane steroid, the 19-Me group formally being transferred to position 4. Furthermore, krempene D contains an unusual C=C bond at C(7) of the pregnane skeleton.