Abstract
The two new triterpene lactones, 11α-hydroxy-28-methoxy-28-oxo-2,3-dinor-18β-olean-12-en-1,4-olide hydrate [C 29 H 44 O 5 .H 2 O, (5)] and 28-methoxy-28-oxo-1,2.-dinor-10α,18β-oleano-9,12-dien-3,10β-olide [C 29 H 42 O 4 , (6)], were obtained according to the method of Zaprutko [Pol. J. Chem. (1995), 69, 1003-1012]. In both compounds, the lactone bridge connects atoms C4 and C10. In (5), the carbonyl group of the lactone bridge is formed by C1 and O1, and in (6), by C3 and O2. In (5), the methyl group at C10 has a β and in (6) an α configuration. The A and B rings are trans-fused in (5), and cis-fused in (6). The bond lengths in ring C indicate double bonds between C12-C13 in (5) and C9-C11 and C12-C13 in (6). The hydroxyl group at C11 in (5) is α oriented. Ring B in (5) has a chair conformation and in (6) a distorted half-chair conformation. Ring C in (5) has a sofa conformation and in (6) a slightly distorted half-chair conformation. Rings D and E have a chair conformation in both compounds and are cis-fused. The asymmetric unit of (5) contains one water molecule, disordered over two positions, making two alternative hydrogen bonds.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Acta Crystallographica Section C Crystal Structure Communications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
