Reactions of Ring C in Glycyrrhetic Acid Derivatives

Sh Rozen*, I. Shahak, E. D. Bergmann

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


The chemistry of the relatively unreactive glycyrrhetic acid (1) ring C was investigated. The enone group in this ring was reduced by diborane to allylic alcohols (6, 7), which can be readily converted into the corresponding homoannular dienes (2, 5). These dienes were also prepared by NaBH4 reduction of the enone group. The epoxidation of the diene 2 leads to the mono‐(12) and di‐(14) epoxides. A new ring C enone system (13) was also obtained. Treatment of the two different tosylhydrazones derivatives (16, 20) with methyllithium gave the conjugated methylene compounds (17, 21). The NMR spectrum of the latter compound was also studied with a shift reagent — Eu(FOD). The mass spectra of the homoannular dienes (2, 5), allylic alcohols (6, 7) and 11‐methylene compounds (17, 21) were studied and some new types of fragmentation were suggested.

Original languageEnglish
Pages (from-to)234-246
Number of pages13
JournalIsrael Journal of Chemistry
Issue number3
StatePublished - 1975


Dive into the research topics of 'Reactions of Ring C in Glycyrrhetic Acid Derivatives'. Together they form a unique fingerprint.

Cite this