• C V Deliwala

      Articles written in Proceedings – Section A

    • Aluminium chloride, a new reagent for the condensation of β-ketonic esters with phenols - Part V. The Condensation of Substituted Resacetophenones with Ethyl Acetoacetate

      C V Deliwala N M Shah

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      The condensation of acetoacetic ester with substituted resacetophenones in the presence of aluminium chloride has been investigated. 5-Ethyl-resacetophenone, 5-bromo-resacetophenone underwent the condensation giving the expected 5-hydroxy-6-acetyl-coumarin derivatives. 4-Acetyl-α-naphthol and 4-propionyl-α- naphthol underwent the condensation but the product obtained was found to be 4-methyl-1: 2-α-naphtha-pyrone, the acyl group being split off during the condensation. Negative results were obtained with 5-nitro-resacetophenone, 5-benzyl-resacetophenone, ω-methoxy-resacetophenone, methyl-β-resacetophenone carboxylate, 4:6-diacetyl-resorcinol and 2:4-diacetyl-resorcinol. The results obtained have been explained; negative groups like-NO2,-CO.Me, etc., hinder the reaction, while positive groups like-C2H5 have no de-activating effect on the course of the reaction.

    • Chemotherapy of bacterial infections - Part V. Synthesis of 2-N1-sulphanilamido-5-alkyl- and 2-N1-sulphanilamido-4-methyl-5-alkyl-thiazoles

      K Ganapathi M V Shirsat C V Deliwala

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      In the course of the attempts to study the effects of the different types of substituents in the molecule of 2-N1-sulphanilamidothiazole, the synthesis of a series of 2-N1-sulphanilamido-5-alkyl- and 2-N1-sulphanilamido-4-methyl-5-alkyl- thiazoles, wherein the alkyl group varies from ethyl to hexyl, have been effected and these compounds are described.

    • Chemotherapy of bacterial infections - Part VII. Synthesis of sulphanilamide derivatives of the pyrimidine group

      K Ganapathi C V Deliwala M V Shirsat

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      Sulphanilylguanidine condensed with ethyl acetoacetate and its α-alkyl derivatives to yield 2-sulphanilamido-4-methylpyrimidone and 2-sulphanilamido-4-methyl-5-alkylpyrimidones respectively. Experiments have been recorded which support these structures and a number of intermediate compounds are described. Ethyl formylacetate condensed with sulphanilyl-guanidine to furnish 2-sulphanilamidopyrimidone. Hydroxymethyleneacetone and hydroxymethylene ethylbutylketone failed to condense with sulphanilylguanidine to yield the corresponding pyrimidines in appreciable yields. Mesityl oxide, on the other hand, has yielded two products which are represented provisionally as the two possible pyrimidine derivatives (XIV) and (XV).

    • Chemotherapy of bacterial infections - Part VIII. Synthesis of carboxylic acid derivatives of 2-sulphanilamidothiazole

      K Ganapathi C V Deliwala M V Shirsat

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      A number of carboxylic acid derivatives of 2-sulphanilamidothiazole with the acid grouping attached directly or through alkyl radicals to the thiazole ring at the positions 4 or 5, are described.

    • The benzoylation of 5-Hydroxy-6-acylcoumarins in presence of pyridine

      N M Shah C V Deliwala

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      The action of benzoyl chloride on 5-hydroxy-6-acyl-coumarins in pyridine solution has been investigated. The reaction leads to the formation of the flavone derivative instead of the expected benzoyloxy derivative. The constitution of the flavone obtained from 5-hydroxy-6-acetyl-coumarin has been confirmed by unambiguous synthesis from the corresponding chalkone by SeO2 reaction. 5-Hydroxy-6-propionyl-coumarin similarly gives the flavone derivative and also reacts in its enolic form, yielding the di-benzoyloxy derivative. 5-Hydroxy-6-butyryl-coumarin gives only the di-benzoyloxy derivative, reacting in its enolic form.

    • Aluminium chloride, a new reagent for the condensation of β-ketonic esters with phenols - Part VI. The condensation of resacetophenone with ethyl α-alkyl-acetoacetates

      C V Deliwala N M Shah

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      The condensation of resacetophenone with several α-substituted acetoacetates with anhydrous aluminium chloride as condensing agent has been investigated. Ethyl α-methyl-, α-ethyl-, α-benzyl-acetoacetates undergo the condensation with the formation of 5-hydroxy-6-acetyl-3-alkyl-coumarin derivatives. Negative results were obtained with ethyl α-prophyl-, α-allyl, α-chloro-acetoacetates, the original ketone being recovered. The results obtained have been discussed.

    • Chemotherapy of bacterial infections - X. 2-Acetsulphanilimido-3-acetsulphanilylthiazolone and 2-Diacetsulphanilylamidothiazole. A new route to sulphathiazole

      C V Deliwala K Ganapathi M V Shirsat

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      2-Aminothiazole condensed with acetsulphanilylchloride in aqueous solution or suspension in the presence of sodium bicarbonate, calcium carbonate or barium carbonate to yield 2-diacetsulphanilylamidothiazole m.p. 128–29°; the same product is also obtained by condensing 2-aminothiazole with two molecular equivalents of acetsulphanilylchloride in pyridine or by condensing 2-acetsulphanilamidothiazole with acetsulphanilylchloride in alkaline solution. This compound on boiling with alcohol isomerises into 2-acetsulphanilimido-3-sulphanilylthiazolone. These two products are hydrolysed by acid or alkali to sulphathiazole in good yield. A process of preparation of sulphathiazole is described.

    • Chemotherapy of Tuberculosis - Part I. Synthesis of possible lipophilic chemotherapeuticals of the sulphonamide and sulphone series derived from fatty acids, including those of the chaulmoogra group

      C V Deliwala K Ganapathi S Rajagopalan

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      Twenty-three compounds have been synthesised as possible lipophilic chemotherapeuticals of the sulphonamide and sulphone series. Among such compounds are the hydnocarpic acid derivatives of N4-n-fatty acyl sulphanilamides, N4, N1-dihydnocarpylsulphanilamide, normal fatty-acyl derivatives of 4-nitro-4′-amino- and 4∶4′-diamino-diphenylsulphones, 4∶4′-bis-adipylamido- and 4∶4′-bis-sebacylamido-diphenylsulphones, and the N4-n-caproyl derivatives of 2-sulphanilamidopyrimidine, 2-sulphanilamido-4-methyl-and 2-sulphanilamido-4∶6-dimethyl pyrimidines.

    • Chemotherapy of Tuberculosis - Part II. Synthesis of N4-acyl-5-alkylsulphathiazolones and 5∶5′-alkylenebis-N4-acyl sulphathiazolones

      C V Deliwala S Rajagopalan

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      An attempt has been made to explore the little investigated but chemically and biologically interesting group of 2-sulphanilamidothiazolones, mostly carrying lipophilic alkyl radicals in the 5-position, for members likely to prove useful in the treatment of tuberculosis and leprosy. In the synthesis of the candidate compounds, emphasis has been laid on the N4-n-fatty acyl derivatives of 2-sulphanilamido-5-substituted thiazolones in the expectation that these would be even more lipophilic than the free sulphanilamidothiazolones themselves.

      A preparative method for the intermediate 2-amino-5-substituted thiazolones, starting with the corresponding mono- and dibasic fatty acids, has been worked out. New 5-substituted pseudothiohydantoins, derived from monobasic acids, are 5-iso propyl-, 5-n-hexyl-, 5-n-tetradecyl-, and 5-phenyl-2-amino-thiazolones. Among new 5∶5′-alkylene-bis-pseudothiohydantoins are 5∶5′-ethylene-bis-2∶2′-aminothiazolone and 5∶5′-hexamethylene-bis-2∶2′-aminothiazolone, prepared from adipic and sebacic acids respectively.

      The following sulphonamidothiazolones have been synthesised: N4-n-butyryl-, N4-n-valeryl-, and the N4-n-caproyl sulphanilyl derivatives of 2-amino-, 2-amino-5-methyl- 2-amino-5-ethyl-, 2-amino-5-isopropyl-, 2-amino-5-n-hexyl-, and 2-amino-5-phenyl-thiazolones; andbis-N4-n-butyryl,bis-N4-n-valeryl- andbis-N4-n-caproyl-sulphanilyl derivatives of 5∶5′-ethylene-bis-2-amino and 5∶5′-hexamethylene-bis-2-aminothiazolones.

      2-Sulphanilamido-5-ethylthiazolone, prepared in the course of this study, differs in its physical characteristics from that of sulphaethylthiazolone as reported by the earlier workers. However, the present sample affords good analytical values and is markedly active in some acute bacterial infections.

    • Chemotherapy of tuberculosis - Part III. Preparation of 5∶5′-dichlorosalicil and heterocyclic derivatives from dichlorosalicil and relateda-diketones

      C V Deliwala S Rajagopalan

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      The highly favourable first reports about the antibacterial merits of 5∶5′-dihalogenated salicils and the essentially sulphonamide-like nature of their action on bacteria, led to an improved method of preparation of 5∶5′-dichlorosalicil or “chlorosalicil” for ascertaining its usefulness in human tuberculosis.

      The ineffectiveness of chlorosalicil onP. pestis in vivo directed attention to the synthesis of a series of biologically interesting heterocyclic ring-systems, particularly the imidazole and pyrazine types, starting with chlorosalicil, benzil, 2∶2′-dichlorobenzil, anisil, diacetyl andorthoquinones, regarded as cyclic α-diketones.

      A total of twenty-eight heterocyclic compounds have been synthesised in this connection. Synthesis of these furnished interesting information regarding the chemistry of imidazoles.

      A few representative heterocyclics, now prepared, have been subjected to examination for efficacyin vivo againstP. pestis, which definitely demonstrated reduction of the original toxicity for infected mice of the initial α-diketones following heterocyclic synthesis from the ketones. However these failed to exhibit any curative action. The failure in experimental plague of the compounds studied has not yet been correlated with their possible anti-mycobacterial activities.

    • Chemotherapy of tuberculosis - Part IV. Synthesis of phthalyl andortho-toluoyl derivatives of the sulphonamides and sulphones as possible mycobacterial antagonists

      C V Deliwala S Rajagopalan

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      In order to fit the sulphonamides and sulphones out better for use in the chemotherapy of tuberculosis and leprosy, synthesis has been effected of a series ofo-phthalic ando-toluic acid derivatives of well-known sulphonamides and disubstituted diphenyl sulphones as possible mycobacterial antagonists.

      Phthalic ando-toluic acid derivatives were chosen for synthesis in view of the recent theory advanced by Shemiakin that the antihæmorrhagic activity of substances of a vitamin K nature, intimately connected with the metabolism of mycobacteria, is due to phthalic acid which arises from the antihæmorrhagic substances. The study of the compounds designed as possible mycobacterial antagonists is expected to shed additional light on the mode of action of antihæmorrhagic compounds and the relation between antihæmorrhagic action and antimycobacterial efficacy.

      The twenty-six compounds synthesised includeo-phthalic acid derivatives of sulphanilamidopyrimidine, sulphanilamido-4-methyl, and sulphanilamido-4: 6-dimethyl pyrimidines and of 4-nitro-, 4-acetamido-diphenyl-sulphones and 4∶4′-diaminodiphenyl sulphone. They also include N4-o-toluoyl derivatives of sulphanilamide, sulphathizoale, sulphathiazoline, sulphapyridine, sulphadiazine, sulphamerazine, 5-bromo-sulphadiazine, and 5-bromosulphamerazine. Other toluic acid derivatives prepared are N4, N1-di-o-toluoyl sulphanilamide, 4∶4′-o-ditoluoylamido-diphenyl sulphone and 4-nitro- and 4-amino-4′-o-toluoylamido-diphenyl sulphones. In addition, N1-o-toluoyl derivatives have been obtained from N4-formyl-, N4-acetyl-, N4-n-butyryl-, N4-n-valeryl-, N4-n-caproyl-, N4-p-heptoyl-, N4-cyclohexoyl and N4-cinnamoyl-sulphanilamides.

    • Chemotherapy of tuberculosis - Part V. Synthesis of some N4-acyl-N1-aryl sulphanilhydroxamides

      C V Deliwala S Rajagopalan

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      A series of sulphanilamides derived from N-carbo and heterocyclic hydroxamides have been synthesised, since a number of N4-acyl sulphanilhydroxamides have been favourably reported on in preliminary experimental bacterial infections. Among the latter wassulphabenamide or N4-caproyl sulphanylhydroxamide, which was said to be effective clinically in streptococcal infections and tuberculosis. This is a new class of sulphanilamides involving the preliminary synthesis of some hitherto unknown substituted aryl- and heterocyclic hydroxamides. The compounds of this series so far prepared are the N4-n-butyryl-, the N4-n-valeryl-, and the N4-n-caproylsulphanilyl derivatives of β-3-chlorophenyl-, β-4-chlorophenyl-, β-2∶5-dichlorophenyl-, and β-3∶4-dichlorophenyl-hydroxylamines.

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