Sandeep Telkar

Design, synthesis and docking studies of new quinoline-3-carbohydrazide derivatives as antitubercular agents.

Three new series of 4-hydroxy-8-trifluoromethyl-quinoline derivatives were synthesized through multi step reactions. All the newly synthesized compounds were characterized by spectral and elemental analyses. The structure of 5j was evidenced by X-ray crystallographic study. The newly synthesized title compounds were evaluated for their antimicrobial activities including antimycobacterial activity. Amongst the tested compounds, 5b, 5e, 5h, 5j, 6c and 7c displayed promising antimicrobial activity. The mode of action of these active compounds was carried out by docking of receptor enoyl-ACP reductase with newly synthesized candidate ligands, 5b, 5e, 5h, 5j and 6c.

Synthesis, characterization and molecular docking studies of some new 1,3,4-oxadiazolines bearing 6-methylpyridine moiety for antimicrobial property.

A new series of 3-acetyl-2-aryl-2H/methyl-5-[3-(6-methylpyridinyl)]-2,3-dihydro-[1,3,4]-oxadiazole derivatives were synthesized from 6-methyl nicotinate through a multistep reaction sequence. The structures of newly synthesized compounds were established on the basis of elemental analysis, IR, 1H NMR, 13C NMR and mass spectral data. Three dimensional structure of the compound 5f was further confirmed by single crystal X-ray analysis. All the synthesized compounds were screened for their antimicrobial activity and antioxidant activity. The final compounds were subjected to molecular docking studies for the inhibition of enzyme L-glutamine: D-fructose-6-phosphate amidotransferase [GlcN-6-P] (EC 2.6.1.16). The in silico molecular docking results are matching with the in vitro studies and they may be considered as good inhibitor of GlcN-6-P synthase.6-methylpyridine.

Synthesis, antimicrobial, analgesic activity, and molecular docking studies of novel 1-(5,7-dichloro-1,3-benzoxazol-2-yl)-3-phenyl-1H- pyrazole-4-carbaldehyde derivatives

Condensation of 5,7-dichloro-2-hydrazino-1,3-benzoxazole 3 with different aromatic acetophenones in methanol using catalytic amount of glacial acetic acid afforded the corresponding 1-phenylethanone(5,7-dichloro-1,3-benzoxazol-2-yl)hydrazones 5a–e in good yield. The compounds 5a–e, when subjected to Vilsmeier–Haack reaction with POCl3 in DMF yielded (5,7-dichloro-1,3-benzoxazol-2-yl)-3-phenyl-1H-pyrazole-4-carbaldehyde derivatives 6a–e. The structural assignments of the compounds 6a–e are based on their spectral data and elemental analysis. The obtained compounds were tested for antimicrobial and analgesic activities, and subjected to molecular docking studies with respect to antimicrobial activity. The compound 6b showed pronounced antimicrobial and analgesic activity and exhibited an interesting binding profile with very high receptor affinity.

Expression of drought responsive genes in pigeonpea and in silico comparison with soybean cDNA library

Pigeonpea, a drought tolerant, semi-arid pulse crop has been investigated for the expression of differentially expressed genes (DEGs) under drought stress. The cDNA library of soybean leaf tissue retrieved from the Unigene database of the NCBI, were compared for in silico expression using IDEG6 web statistical tool. A list of 52 non-redundant DEGs consisting of 11 up-regulated and 41 down-regulated was obtained. Among these, more photosynthesis and light harvesting proteins were down-regulated in drought stress conditions. Pathways were assigned based on KEGG database, revealing 32 genes involved in 17 metabolic pathways. Homologous sequences of six up-regulated genes namely, ADF3, APB, ASR, DLP, LTP1, and UGE5 were then used for quantitative reverse transcription PCR (qRT-PCR) in pigeonpea. The qRT-PCR result revealed the significant up-regulation of dehydrin-like protein (DLP) (5.02 log2 fold) and down-regulation of acid phosphatase class B family protein (APB) (9.43 log2 fold) and non-specific lipid transfer protein 1-like (LTP1) (18.81 log2 fold) in pigeonpea water-stressed leaf sample compared to well-watered leaf samples. No significant difference was observed in the stressed root compared to the stressed pigeonpea leaf sample except that APB showed an up-regulation of 11.35 log2 fold change.

Synthesis and anti-inflammatory evaluation of some new 3,6-disubstituted-1,2,4-triazolo-[3,4-b]-1,3,4-thiadiazoles bearing pyrazole moiety

In the present study, a new series of 3,6-disubstituted-1,2,4-triazolo-[3,4-b]-1,3,4-thiadiazoles (4aj) have been synthesized by condensing 3-substituted-4-amino-5-mercapto-1,2,4-triazoles (1a–b) with various 3-substituted-pyrazole-4-carboxylic acids (3a–e) in the presence of POCl3. The structures of newly synthesized compounds were characterized by elemental analysis, IR, 1H NMR, 13C NMR, and mass spectroscopic studies. Structure of the compound 4b was also confirmed by recording the single crystal X-ray structure. All the synthesized compounds were screened for their anti-inflammatory activities by carrageenan induced paw edema method. Anti-inflammatory screening indicated that, compounds 4d, 4e, and 4h were found to be biologically active whereas remaining compounds showed poor anti-inflammatory activity. Also molecular docking studies were also performed for compounds which showed good anti-inflammatory activity.

Type II diabetes-related enzyme inhibition and molecular modeling study of a novel series of pyrazolone derivatives

AbstractInhibitors of alpha-amylase are targets for the development of novel drugs for the treatment of diabetes and obesity. Alpha amylase is an enzyme which increases the bio availability of glucose in the blood. Hence, the inhibition effects of alpha amylase of 2-[1-(4-isobutylphenyl)ethyl]-5-methyl-4-[2-(aryl-substituted)hydrazinylidene]-2,4-dihydro-3H-pyrazol-3-one (4a–l) were investigated, among them compounds 4d, 4f, 4a, and 4g have displayed good inhibitory activity. The compounds with significant results were further evaluated for their molecular modeling study using in silico method. The new series of compounds were synthesized by solvent-free microwave irradiation method and were characterized by spectral and analytical data.

Synthesis of a series of novel 2,5-disubstituted-1,3,4-oxadiazole derivatives as potential antioxidant and antibacterial agents

A series of novel 2,5-disubstituted-1,3,4-oxadiazole derivatives were synthesized and screened for their antimicrobial and antioxidant activities. The assay indicated that compounds 3c, 3d, and 3i exhibited comparable antibacterial and antioxidant activity with first-line drugs. The structure activity relationship and molecular docking study of the synthesized compounds are also reported.

Synthesis, antibacterial and antitubercular activity of novel Schiff bases of 2-(1-benzofuran-2-yl)quinoline-4-carboxylic acid derivatives

Novel Schiff bases of 2-(1-benzofuran-2-yl)quinoline-4-carboxylic acid derivatives 5a–5e were synthesized by the reaction of 2-(1-benzofuran-2-yl)quinoline-4-carbohydrazide 3 with substituted aromatic aldehydes 4a–4e in presence of catalytic amount of acetic acid. Reaction of methyl 2-(1-benzofuran-2-yl)-quinoline-4-carboxylate 2 with hydrazine hydrate upon refluxing in ethanol for 4 h gave the key intermediate, hydrazide compound 3. All newly synthesized compounds were characterized by IR, NMR and Mass spectra and screened for antibacterial and antitubercular activity. Among the tested compounds carbohydrazide 3 and the compounds 5a and 5e exhibited high activity against S. aureus and E. faecalis respectively with MIC 0.064 mg/mL. Compound 5e demonstrated significant activity against S. aureus and E. faecalis with MIC 0.064 mg/mL. The antibacterial tests revealed hydrazide derivative 3 sensitivity at 25 μg/mL, showing high activity among the synthesized compounds.

Synthesis and antimicrobial activity of fused isatin and diazepine derivatives derived from 2-acetyl benzofuran

Acetyl benzofurans 1a, 1b reacted with isatins 2a–2f in the presence of pyridine to give corresponding 3-[2-(1-benzofuran-2-yl)-2-oxoethyl]-3-hydroxy-1,3-dihydro-2H-indol-2-one derivatives 3a–3l. Dehydration of the latter in acidic media led to the corresponding α,β-unsaturated ketones 4a–4l. The structures of newly synthesized compounds 3a–3l and 4a–4l were established on the basis of analytical and spectral data. The synthesized compounds were screened for their antibacterial and antifungal activities. Compounds 5d, 5f, and 5h displayed excellent antimicrobial activity. The synthesized compounds were studied for docking on the enzyme, Glucosamine-6-phosphate Synthase.

Synthesis, characterization, and antimicrobial activity of new benzofuran derivatives

A novel series of (5-substituted-1-benzofuran-2-yl)(2,4-substituted phenyl)methanones (4a–4i) have been prepared by the Knoevenagel condensation of (5-substituted-1-benzofuran-2-yl)(2,4-substituted phenyl)methanone (3a–3i) with Meldrum’s acid. The structures of the synthesized compounds were characterized by different spectroscopic techniques. All newly synthesized compounds were screened for antimicrobial activity.