Isolation and identification of l/d-lactate-conjugated bufadienolides from toad eggs revealing lactate racemization in amphibians.
Org Biomol Chem
; 15(26): 5609-5615, 2017 Jul 05.
Article
in En
| MEDLINE
| ID: mdl-28639665
ABSTRACT
Three pairs of bufadienolide l/d-lactate epimers (1-6) were isolated from the eggs of the toad Bufo bufo gargarizans. The structures were elucidated by using spectroscopic methods, X-ray diffraction analysis and a modified Mosher's method. Compounds 1-6 represent the first occurrence of lactate-conjugated bufadienolides in nature, and illustrate the existence of an enzyme-controlled epimerization from l- to d-lactate in amphibians. The biosynthetic pathways, in which two key enzymes might be involved (i.e., lactate racemase and acyltransferase), were proposed. In addition, the biological assays revealed that compounds 1-4 are potent cytotoxic agents against human gastric cancer cells BGC-823 and human lung cancer cells A549 with IC50 values in a range of 8.0 to 80.0 nM.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Ovum
/
Bufanolides
/
Lactic Acid
/
Antineoplastic Agents
Type of study:
Diagnostic_studies
Limits:
Animals
/
Humans
Language:
En
Journal:
Org Biomol Chem
Journal subject:
BIOQUIMICA
/
QUIMICA
Year:
2017
Document type:
Article