New antitrypanosomal tetranotriterpenoids from Azadirachta indica. (49/84)

Organic extracts of the leaves of Azadirachta indica A. Juss. yielded ten antitrypanosomal terpenoids. Three of these (1-3), are novel and are derivatives of nimbolide and nimbin. They were extracted from chloroform fraction of methanol extract. These compounds were found to exhibit strong antitrypanosomal activities against Trypanosoma brucei rhodesiense with MIC values ranging of 6.9, 15.6 and 7.8 microg/ml respectively and were more active than Cymerlarsan (a standard drug), which had an MIC value of 187.5 microg/ml when tested against T. b. rhodesiense. The structures were elucidated by spectroscopic methods including; NMR, MS, UV and IR.  (+info)

Phragmalin-type limonoid orthoesters from the twigs of Swietenia macrophylla. (50/84)

Eleven new phragmalin-type limonoids, swietenitins N-X (1-11), together with a known one, epoxyfebrinin B (12), were isolated from the twigs of Swietenia macrophylla. The structures of the new compounds were established on the basis of spectroscopic methods, and that of compound 1 was confirmed by single-crystal X-ray diffraction. The stereochemistry of epoxyfebrinin B (12) was fully assigned in this study.  (+info)

In vitro acaricidal activity of neem (Azadirachta indica) seed extracts with known azadirachtin concentrations against Rhipicephalus microplus. (51/84)

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Development of Neh2-luciferase reporter and its application for high throughput screening and real-time monitoring of Nrf2 activators. (52/84)

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Increased production of azadirachtin from an improved method of androgenic cultures of a medicinal tree Azadirachta indica A. Juss. (53/84)

Present report is the first direct evidence of azadirachtin production in androgenic haploid cultures of Azadirachta indica, a woody medicinal tree. Anther cultures at early-late-uninucleate stage of microspores were established on MS medium with BAP (5 muM), 2,4-D (1 muM) and NAA (1 muM) containing 12% sucrose. The calli, induced, were further multiplied on 2,4-D and Kinetin media. Shoots, differentiated on BAP (2.2 muM) + NAA (0.05 muM) medium, were elongated on MS + BAP (0.5 muM) and multiplied on MS + BAP (1 muM) + CH (250 mg/l). Thereafter, the shoots were rooted on (1/4) MS + IBA (0.5 muM). Cytological analysis of the calli and regenerants have confirmed their haploid status with the chromosome number as 2n = x = 12. The haploid cell lines and leaves from in vitro grown plantlets were analyzed for azadirachtin by RP-HPLC and mass spectroscopy. Maximum azadirachtin (728.41 mug/g DW) was detected in calli supporting best shoot proliferation while least (49 mug/g DW) was observed in an undifferentiated line from maintenance medium. This study has brought us a step closer to develop genetically pure lines that could serve as new and attractive alternative ways of homogeneous controlled production of high value compounds, round the year, independent of geographical and climatic barrier.  (+info)

seco-limonoids and quinoline alkaloids from Raputia heptaphylla and their antileishmanial activity. (54/84)

A novel seco-limonoid, rel-(1S,5R,9S,7R,8S,9R,10S,11R,13S,14R,15R,17R)-11,19-dihydroxy-7-acetoxy-7-deoxo ichangin (raputiolide) (1), and two novel quinolone alkaloids N-methyl-2-phenoxyquinolin-4(1H)-one (heptaphyllone A) (2) and 6-methylbenzofuro[2,3-b]quinolin-4(1H)-one (heptaphyllone B) (3), along with the known seco-limonoid ichangin (4), were isolated from Raputia heptaphylla PITTIER (Rutaceae) stem bark. Five known alkaloids, N-methyl-8-methoxyflindersine (5), skimmianine (6), kokusaginine (7), dictamnine (8) and flindersiamine (9), were also isolated from R. heptaphylla leaves. Their structures were established on the basis of full spectroscopic data interpretation supported by data from the pertinent literature. seco-Limonoid 1 configuration was determined by enhanced nuclear Overhauser effect spectroscopy (NOESY) experiments and density functional theory (DFT) molecular modeling. The antileishmanial effect of the isolated compounds was evaluated on Leishmania Viannia panamensis (promastigotes and amastigotes). Whereas alkaloids 2-3, 6-8 and limonoid 4 exhibited no significant parasitocide activity against internalized L. (V.) panamensis amastigotes, limonoid 1 and alkaloid 5 had leishmanicidal activity on intracellular amastigotes (EC(5)(0): 8.7 microg/ml) and promastigotes (EC(50): 14.3 microg/ml), respectively.  (+info)

Limonoids and triterpenoids from the seeds of Melia azedarach. (55/84)

Three limonoids (1-3), and two triterpenes (4) and (5), along with twelve known compounds, were isolated from the seeds of Melia azedarach. Their structures were established on the basis of extensive spectroscopic analysis. Compound 3 showed moderate antimicrobial activity.  (+info)

Regulation of apoptotic effects by erythrocarpine E, a cytotoxic limonoid from Chisocheton erythrocarpus in HSC-4 human oral cancer cells. (56/84)

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