L. Prakash

ANGULAR HETEROCYCLES: STUDIES IN THESYNTHESIS OF BENZO[a][1,4]BENZOTHIAZINO-[3,2-C]PHENOTHIAZINES AND5H-BENZO[a]PHENOTHIAZIN-5-ONES

Abstract The substituted benzo[a][1,4]benzothiazino[3,2-C]phenothiazines and 5H-benzo[a]phenothiazin-5-ones were prepared by the condensation of 2,3-dichloro-5-nitro-1,4-napthoquinones 1 with 2-amino-3,5disubstituted benzenethiols 2a and their zinc salts respectively. The resulting compounds were subjected to reduction, methylation and acetylation. Some of these compounds were screened for their antimicrobial activity against bacteria S. aureus and E. coli and fungi Aspergillus niger, Aspergillus flavus, Fusarium moniliformae and Curvularia lunata.

A Step Forward in the Field of Drug Design: 1,5-Benzothiazepines and Their Nucleosides

Abstract(±)cis-2-(4-methoxyphenyl)-3-hydroxy/methoxy-6-methoxy/8-methoxy-2,3-dihydro-1,5-benzothiazepin-4-[5H/5-chloroacetyl/5-(4′-methylpiperazino-1′)acetyl]-ones and nucleosides viz; (±)cis-2-(4-methoxyphenyl)-3,6-dimethoxy-2,3-dihydro-1,5-benzothiazepin-4-[5-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)]-one and (±)cis-2-(4-methoxyphenyl)-3,8-dimethoxy-2,3-dihydro-1,5-benzothiazepin-4-[5-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)]-one have been synthesized by the condensation of substituted-2-aminobenzenethiols with methyl (±)trans-3-(4-methoxyphenyl)glycidate in xylene and by stirring the 3-methoxy derivative of 1,5-benzothiazepin-4(5H)-ones with sugar namely β-D-ribofuranosyl-1-acetate-2,3,5-tribenzoate at 155–160 °C in vacuo for 10 hours, respectively.The synthesized compounds have been characterized by the elemental analyses and spectral data and screened for their antimicrobial activity.

SYNTHESIS OF SOME 5-FURFURYL PYRIDO[2,3-d] PYRIMIDINES AND 1-ETHYL-5-FURFURYL PYRIDO[2,3-d] PYRIMIDINES AS POSSIBLE ANTITUMOR & ANTICANCER AGENTS

Abstract Synthesis of some novel 5-furfuryl pyrido[2,3-d]pyrimidines was carried out by the condensation of 2-amino-3-cyano-4-furfuryl-6-substituted pyridine with various arylisothiocy-anates, thiourea and carbondisulphide. These compounds on treatment with ethylbromide using phase transfer catalyst gave 1-ethyl-5-furfuryl pyrido[2,3-d]pyrimidines. The structure of the compounds has been established by elemental, IR and NMR studies. The compounds thus synthesized were screened for their antimicrobial activity.

SYNTHESIS OF SOME NOVEL 1-AZAPHENOTHIAZINES AND THEIR MESOIONICS AS ANALOGUES OF POTENT CNS-DEPRESSANTS

Abstract 1-Azaphenothiazine derivatives were synthesized by the condensation of the zinc salt of substituted 2-aminobenzenethiols and 2-chloro-3, 5-dinitropyridines. Mesoionic compounds, viz. substituted 1-hydroxy-2-chloroacetyl-, piperidinoacetyl-, and piperazinoacetyl-4-nitro-6-thia-10b-aza-2a-zoniaaceanthrylene hydroxide inner salts and substituted 1-hydroxy-4-nitro-6-thia-10b-aza-2α-azoniaaceanthrylene hydroxide inner salts were prepared. The synthesized compounds were characterized by elemental analyses, IR and 1H NMR and were screened for antimicrobical activity.

SYNTHESIS OF NOVEL THIOXODERIVATIVES OF PYRIDO[2,3-d]PYRIMIDINES AND THEIR NUCLEOSIDES AS POSSIBLE ANTICANCER AGENTS

Abstract Synthesis of some 2-thioxo-3,5,7-trisubstituted pyrido[2,3-d]pyrimidine-4(1H)-ones and corresponding nucleosides viz. 2-thioxo-3,5,7-trisubstituted-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)pyrido[2,3-d]-pyrimidine4 (1H)-ones is reported. The results of antimicrobial activities are also reported. The structures of the compounds have been established by elemental, IR and NMR analyses.

Synthesis of some novel fluoro-substituted benzo[a]phenothiazines and their nucleosides as possible antimicrobial agents

Abstract 6-(2-Methoxy-5-methyl/2-methoxy-4-chloro-5-methyl anilino)-9-fluoro-5H-benzo-[a]phenothiazine-5-ones/thiones, 12H-benzo[a]phenothiazine-5-ols, 5-acetoxy-12H-benzo[a]phenothiazines, 5-methoxy-12H-benzo[a]phenothiazines and nucleosides viz; N-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-6-(2-methoxy-5-methyl/2-methoxy-4-chloro-5-methyl anilino)-9-fluoro-5-acetoxy benzo[a]phenothiazines and 9-fluoro-5-methoxy benzo[a]phenothiazines have been synthesized. All the synthesized compounds were tested for their antimicrobial activity. Structural elucidation has been made on the basis of elemental analysis IR, 1 H and 19 F NMR studies.

CHEMICAL SYNTHESIS AND BIO-SCREENING OF BENZO-PHENOTHIAZINES, BEARING SIDE CHAIN AT THE 6-POSITION

Abstract Some new anilino-5H-benzo[a]phenothiazin-5-ones (III) were synthesized by the condensation of 2-(4-bromoanilino)-3-chloro-1,4-naphthoquinone (II) with corresponding zinc mercaptide (I). Derivatives of compound (III) were prepared by its reduction, methylation and acetylation and were screened for antimicrobial evaluation. Structural assignments were done on the basis of elemental analyses, IR and 1H NMR.

SYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL EVALUATION OF THIONE AND DITHIONE DERIVATIVES OF PYRIDO[2,3-d]PYRIMIDINES

Abstract Synthesis of some newer pyrido[2,3-d]pyrimidine derivatives was carried out by the condensation of 2-amino-3-cyano-4,6-disubstituted pyridine with different arylisothiocyanates, thiourea and carbon disulfide. The compounds, thus obtained were put to elemental and physical analyses and were tested for antimicrobial activities.

Synthesis of thiourea derivatives of s-triazine and their antimicrobial activity

Synthesis of trisubstituted derivatives of s-triazine containing thiourea group by the replacement reaction. The elemental analysis, IR, 13C, 19F and 1H NMR spectral data confirm the structure of the compounds. The synthesized compounds have been tested for antimicrobial activity.