Unexpected Formation of 11(9â7)-abeo-Steroid Skeleton in Synthetic Studies toward Batrachotoxin.
Chem Pharm Bull (Tokyo)
; 72(4): 360-364, 2024.
Article
in En
| MEDLINE
| ID: mdl-38569844
ABSTRACT
Batrachotoxin (1) is a potent cardio- and neurotoxic steroid isolated from certain species of frogs, birds, and beetles. We previously disclosed two synthetic routes to 1. During our synthetic studies toward 1, we explored an alternative strategy for efficiently assembling its 6/6/6/5-membered steroidal skeleton (ABCD-ring). Here we report the application of intermolecular Weix and intramolecular pinacol coupling reactions. While Pd/Ni-promoted Weix coupling linked the AB-ring and D-ring fragments, SmI2-mediated pinacol coupling did not cyclize the C-ring. Instead, we discovered that SmI2 promoted a 1,4-addition of the α-alkoxy radical intermediate to produce the unusual 11(9â7)-abeo-steroid skeleton. Thus, this study demonstrates the convergent assembly of the skeleton of the natural product matsutakone in 11 steps from 2-allyl-3-hydroxycyclopent-2-en-1-one.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Samarium
/
Batrachotoxins
/
Glycols
/
Iodides
Language:
En
Journal:
Chem Pharm Bull (Tokyo)
Year:
2024
Document type:
Article
Country of publication: