Nirup B. Mandal

Synthesis of a novel quinoline derivative, 2-(2-methylquinolin-4-ylamino)-N-phenylacetamide—a potential antileishmanial agent

Some novel quinoline derivatives were prepared and tested for antileishmanial activity. 2-(2-Methylquinolin-4-ylamino)-N-phenylacetamide (2) was found to be significantly more active than the standard antileishmanial drug sodium antimony gluconate (SAG) in reducing the parasite load both in the spleen and liver at a much lower concentration in hamster models. The results suggest that the compound could be exploited as an antileishmanial drug.

Polyoxypregnane glycosides from the flowers of Dregea volubilis.

Three novel polyoxypregnane glycosides, volubiloside A, B and C (1-3), were isolated from the flowers of Dregea volubilis Linn., and their structures were elucidated as drevogenin D-3-O-beta-D-glucopyranosyl (1-->4)-6-deoxy-3-O-methyl-beta-D-allopyranosyl (1-->4)-beta-D-cymaropyranosyl (1-->4)-beta-D-cymaropyranoside, drevogenin D-3-O-beta-D-glucopyranosyl (1-->4)-6-deoxy-3-O-methyl-beta-D-allopyranosyl (1-->4)-beta-D-cymaropyranosyl (1-->4)-beta-D-digitoxopyranoside and drevogenin P-3-O-beta-D-glucopyranosyl (1-->4)-6-deoxy-3-O-methyl-beta-D-allopyranosyl (1-->4)-beta-D-cymaropyranosyl (1-->4)-beta-D-cymaropyranoside, respectively, on the basis of extensive NMR experiments, MALDI-TOF MS, and some chemical strategies.

Evaluation of the wound healing activity of methanol extract of Pedilanthus tithymaloides (L.) Poit leaf and its isolated active constituents in topical formulation

ETHNOPHARMACOLOGICAL RELEVANCE Pedilanthus tithymaloides leaves are widely used in Indian medicine to heal wounds, burn, mouth ulcers. However, systematic evaluation of these activities is lacking. Thus, the present study aimed to assesses the wound healing activity of Pedilanthus leaves and its isolated constituents in topical ointment formulation. MATERIALS AND METHODS Bioassay-guided chromatographic fractionation of the methanol extract of leaves resulted in the isolation of 2-(3,4-dihydroxy-phenyl)-5,7-dihydroxy-chromen-4-one and 1, 2-tetradecanediol, 1-(hydrogen sulfate), sodium salt. The ointment formulation of methanol extract (2.5%, 5% w/w) and isolated compounds (0.25% w/w) was prepared and evaluated on excision, incision and dead space wound models in rats. The effects of formulations on wound healing were assessed by the rate of wound closure, period of epithelialization, tensile strength, granulation tissue weight, hydroxyproline content and histopathology. RESULTS Significant wound healing activity was observed with methanol extract and isolated constituents. Topical application of isolated compound ointments caused faster epithelialization, significant wound contraction (95.41%), and better tensile strength (565.33 g) on 16 post-wounding day, while 5% extract showed wound epithelialization with 95.55% contraction on 18th post-wounding day, better than the control group (76.39% on 22 day). The tensile strength of incision wound was significantly increased in extract and compound treated animals. Moreover, in dead space model the extract significantly increased granuloma tissue weight, tensile strength and hydroxyproline content. The tissue histology of ointment treated groups showed complete epithelialization with increased collagenation, compared to the povidone-iodine group. CONCLUSIONS The results validated the traditional use of Pedilanthus tithymaloides for cutaneous wound management.

Triterpene glycosides from the bark of Anthocephalus cadamba

Two triterpenoid glycosides, glycosides A and B were isolated from the bark of Anthocephalus cadamba and defined as 3-O-[α-L-rhamnopyranosyl]-quinovic acid-28-O-[β-D-glucopyranosyl] ester and 3-O-[β-D-glucopyranosyl]-quinovic acid-28-O-[β-D-glucopyranosyl] ester respectively.

Synthesis of indolylquinolines under Friedel-Crafts reaction conditions

Abstract A one-pot synthesis of some novel indolylquinoline analogues of biological interest using indole or its 5-subtituted derivatives as substrates under Friedel-Crafts acylation conditions is reported. The synthesis of the compounds was accomplished by the employment of excess amounts of the substrates and higher temperature. The complete structure of the derivative obtained by using indole as substrate and dichloroacetyl chloride as acylating agent was unequivocally established as 2-(2″-dichloroacetamidobenzyl)-3-(3′-indolyl)-quinoline 2a by single crystal X-ray analysis. The structures of other similar indolylquinolines 2b-2e and 3 were defined by spectroscopic analysis. The mechanism of formation of the analogues has also been rationalised

Combination Therapy with Indolylquinoline Derivative and Sodium Antimony Gluconate Cures Established Visceral Leishmaniasis in Hamsters

ABSTRACT 2-(2″-Dichloroacetamidobenzyl)-3-(3′-indolylquinoline), designated indolylquinoline derivative A, reduced the splenic and the liver parasite burdens by >93.0% in Leishmania donovani-infected hamsters, whereas sodium antimony gluconate (SAG) reduced the burdens approximately 80.0%. Complete clearance of parasitemia from the livers and spleens was noticed when infected animals received indolylquinoline derivative A plus SAG, suggesting that indolylquinoline derivative A has potential as a new agent for sole or conjunctive therapy for leishmaniasis.

Chemistry and Biology of the Triterpenes and Saponins from Seeds of Mimusops elengi

ABSTRACT Mimusops elengi Linn. (N.O. Sapotaceae), a tree indigenous to India, has a long history of being used in traditional medicine. The primary compounds of interest in this plant are the triterpenes and triterpene glycosides. The triterpene, mimusopic acid, possessing the novel migrated oleanane skeleton, mimusopane, exhibits anti-HIV reverse transcriptase activity and modification of this novel compound may lead to more potent bioactive substances. Moreover, the saponins present also demonstrated to be antifungal against some human pathogens. The compounds isolated, characterized and bioactivity evaluated are presented in the form of a review.

Synthesis of 2-methylindole analogues and skatole dimers under friedel-crafts reaction conditions

Abstract A one pot synthesis of 2-methy lindole analogues and skatole dimers of biological interest using excess amounts of the substrates and the catalyst and higher temperature under Friedel-Crafts acylation conditions is reported. The products were defined by spectroscopic and single crystal X-ray analysis. Rationalization for the formation of the products has also been attempted.

Novel friedel - crafts reactions of some arenes

Abstract The novel secondary Friedel-Crafts acylation products of the arenes, dimethyl resorcinol, m-xylene, m-methylanisole and m-chlorotoluene using dichloro-acetylchloride and anhydrous AlCl3 are described. The formation of the unexpected products has been shown to depend on the nucleophilicity of the arene and the electrophilicity of the acyl carbonyl of the initially formed acylated product. Higher molar proportion of the arene and sometimes elevated temperature are necessary for generation of the products. The reaction pathway has been shown to be incluenced by the formation of the possible complex of AlCl3 and dichloro-acetylchloride with the groups adjacent to the dichloroacetyl function, especially at higher temperature. Dimethylresorcinol yields the unique products 4, 5, 6, 7 and 9 and m-xylene, m-methylanisole and m-chlorotoluene furnish 10, 13 and 15 respectively. Electronic factors responsible for generation of the products and rationalisation of their formation are discussed.

One pot synthesis of 2,2-dichloro-1,1-bis(4-dialkylaminophenyl)ethylenes by Friedel-Crafts acylation

A simple method is described for the preparation of 2,2-dichloro-1,1-bis(4-dialkylaminophenyl)ethylenes from dialkyl anilines by Friedel-Crafts reaction using AlCl3 as Lewis acid and dichloroacetyl chloride as acylating agent.