ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The leaves and roots of Cipadessa cinerascens (PELL.) HAND-MAZZ (Meliaceae), a shrub distributed in Southwest China, are used for the treatment of rheumatism, malaria, scald and skin itch.1) From the leaves of C. cinerascens flavonoids and their glucosides were isolated. [2][3][4] From the leaves and bark of C. cinerascens, novel limonoids, cipadesins A-C, were obtained during our study.5) The continued study led to the isolation of three new limonoids, cipadesins D-F (1-3), together with 8,15-dihydroxy-13E-labdane, 6) b-sitosterol and b-daucosterol. 168.8, 170.4, 170.8), the left twenty six 13 C-NMR signals indicated that 1 may be a limonoid. The presence of b-substituted furan ring (d H 6.42, 7.44, 7.59; d C 108.8, 121.1, 140.4, 143.4) and four tertiary methyl groups as well as the HMBC experiment ( Fig. 2) showed that 1 was trijugin type limonoid, [7][8][9] characterized by a five-membered ring C with an exocyclic carbonyl at C-9. Three acetyl groups were located at C-2, C-3 and C-12 by the HMBC cross signals between H-2 (d H 5.25), OAc (d C 170.4), between H-3 (d H 5.14), OAc (d C 170.8), and between H-12 (d H 5.55), OAc (d C 168.8). The relative stereochemistry of 1 was determined by NOESY experiments (Fig. 2). X-Ray crystallographic analysis of 1 (Fig. 3) confirmed the structure.The UV, IR, 1 H-and 13 C-NMR spectral data of cipadesins E, F (2, 3) were similar to those of 1, suggesting they are all limonoids.Cipadesin E (2) was isolated as white powder. Its molecular formula C 31 H 38 O 12 was provided by the quasi-molecular ion peak at m/z 625.2283 [MϩNa] ϩ in the HR-ESI-MS. The presence of a ketonic carbonyl group and four ester carbonyl groups were recognized from the IR peak at 1746 cm Ϫ1 , and 7) showed that 2 was trijugin type limonoid (Fig. 2). A hydroxyl group resonated at d 4.72 gave HMBC correlations with C-9 and C-11, and NOESY correlation with H-12a, allowing it to be assigned to C-11a. The remaining structure was confirmed by HMBC and NOESY experiments (Fig. 2).Cipadesin F (3) was isolated as white powder. Its molecular formula C 31 H 40 O 11 was concluded from the quasi-molecular ion peak at m/z 611.2471 [MϩNa] ϩ in the HR-ESI-MS. Four ester carbonyl groups were revealed by the IR peak at 1739 cm Ϫ1 and 13 C-NMR signals at d 175.0, 170.7, 170.2 and 169.9. HMBC experiment (Fig. 2) showed that 3 was methyl angolensate type limonoid, 10,11) characterized by a six-membered ring C connected with ring A by C-9 and C-10. The structure of 3 was determined by NMR data in DMSO-d 6 . The hydroxyl group resonated at d 4.72 was as- D-F (1-3), together with 8,15-dihydroxy-13E-labdane, b b-sitosterol and b b-daucosterol, were isolated from the leaves and bark of Cipadessa cinerascens. Their structures were elucidated by spectral evidence. X-Ray crystallographic analysis confirmed the structure of 1.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.