Prashant Gahtori

Antifungal activity, SAR and physicochemical correlation of some thiazole-1,3,5-triazine derivatives.

OBJECTIVE Present research communication was towards the investigation of antifungal minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) activity of some substituted clubbed thiazole-1,3,5-triazines derivatives and effect of physicochemical properties on bioactivity. MATERIAL AND METHODS MIC and MFC were evaluated against Candida albicans, Candida glabrata, Cryptococcus neoformans and Aspergillus niger using modified microdilution method recommended by CLSI. Cytotoxicity was determinate on the viability of marine shrimp larvaes. SAR and physicochemical correlations were studied by Molinspiration software. RESULTS The 5 and 9 derivatives showed an excellent antifungal activity with MIC lower than fluconazole and equivalent to amphotericin B specially against C. albicans and C. glabrata. The toxicity of these two derivatives was non-existent for 5 and moderate for 9 at the used concentration. SAR study around prototype molecule suggests that presence of di-hydrophobic fragment on 1,3,5-triazine is necessary for antifungal activity than halogen substituted aromatic amine. CONCLUSION On the basis of selectivity, potency and non-toxicity, we have obtained two molecules (5 and 9) as prospective leads for further research work on 1,3,5-triazine as antifungal drug.

Antimalarial evaluation and docking studies of hybrid phenylthiazolyl-1,3,5-triazine derivatives: A novel and potential antifolate lead for Pf-DHFR-TS inhibition

Present communication deals with the docking study of hybrid phenyl thiazolyl-1,3,5-triazine analogues (1a-36d) on three selected different binding site viz., α, β and γ of wild type Pf-DFHR-TS. In admiration of excellent H-bond scoring, with regard to cycloguanil and to a large extent similar scoring with WR99210, compound 4a, 12b, 21c, 23c, 28d, 29d, 34d, and 35d were selected for in vitro antimalarial activity against 3D7 strain of Plasmodium falciparum. Findings from the study disclose that a significant correlation was exist between in vitro results and in silico prediction (r(2)=0.543). Furthermore, investigation of structure-activity relationships elucidate crucial structural requirement for site specific binding of ligands.

Synthesis and antibacterial evaluation of series of novel tri-substituted-s-triazine derivatives

Two novel series of s-triazine derivatives (6a–e and 7a–f) were synthesized with various aromatic and heterocyclic amines. The synthesized compounds were subsequently evaluated for their in vitro antibacterial activity against three gram-positive viz. Bacillus subtilis (NCIM-2063), Bacillus cereus (NCIM-2156), Staphylococcus aureus (NCIM-2079) and gram-negative bacteria viz. Pseudomonas aeruginosa (NCIM-2036), Escherichia coli (NCIM-2065) and Klebseilla pneumoniae (NCIM-2706) by the broth dilution method as recommended by the National Committee for Clinical Laboratory Standards (NCCLS) using streptomycin as reference standard. Structures of the synthesized compounds were elucidated on the basis of elemental analyses and spectral data.

Antimalarial activity and docking studies of novel bi-functional hybrids derived from 4-aminoquinoline and 1,3,5-triazine against wild and mutant malaria parasites as pf-DHFR inhibitor

Bi-functional conjugates comprised of 4-aminoquinoline and 1,3,5-triazine were synthesized through facile synthetic routes. These compounds were rigorously screened for determination of their antimalarial activity against wild and mutant cultured Plasmodium falciparum. The results disclosed that the conjugates have considerable antimalarial activity against both wild and mutant parasites with marked variation on changing the pattern of substitutions. The observed activity profiles were additionally substantiated by docking studies on both wild and quadruple mutant P. falciparum dihydrofolate reductase thymidylate synthase (pf-DHFR-TS).

4-Aminoquinoline-1,3,5-triazine: Design, synthesis, in vitro antimalarial activity and docking studies

A series of hybrid 4-aminoquinoline 1,3,5-triazine derivatives was synthesized and their chemical structure were confirmed by 1H-NMR, 13C-NMR, FT-IR and mass spectrometric analyses. In vitro antimalarial activity of these compounds was evaluated against chloroquine-sensitive (3D-7) and chloroquine resistant (RKL-2) strains of P. falciparum. Results showed that all compounds had considerable antimalarial activity against both the strains and further docking studies were performed on both wild type (1J3I.pdb) and quadruple mutant (N51I, C59R, S108 N, I164L, 3QG2.pdb) pf-DHFR-TS to quantify the structural parameter necessary for the activity.

Synthesis, SAR and antibacterial activity of hybrid chloro, dichloro-phenylthiazolyl-s-triazines

A series of hybrid novel chloro (1a-9a) and dichloro (10b-18b) phenylthiazolyl-s-triazine were synthesized and subsequently subjected to their antibacterial activity against three gram positive viz. Lactobacillus casei (NCIM-2651); Bacillus cereus (NCIM-2458); Staphylococcus aureus (NCIM-2120) and three gram negative viz Salmonella typhimurium (NCIM-2501); Escherichia coli (NCIM-2065); Klebsiella aerogenes (NCIM-2098). The SAR studies around the lead compound revealed that introduction of electron withdrawing groups and amino (-NH-) and mercapto (-S-) linker bridge seemed more promising towards antibacterial activity. Moreover, the virtual Molinspiration screenings are in compliance with Ghoses rule.

Design, Synthesis, Antibacterial Activity, and Molecular Docking Studies of Novel Hybrid 1,3- Thiazine-1,3,5-Triazine Derivatives as Potential Bacterial Translation Inhibitor

Some novel hybrid 1,3‐thiazine‐1,3,5‐triazine derivatives were synthesized and tested for antibacterial activity. Compounds 8c and 8f were found active against Gram positive and Gram negative microorganisms. Molecular docking studies have been performed on eubacterial ribosomal decoding A site (Escherichia coli 16S rRNA A site) to rationalize the probable mode of action, binding affinity, and orientation of the molecules at the active site of receptor. The structures of all these newly synthesized compounds were confirmed by their elemental analyses and spectral data techniques viz. IR, 1H NMR, 13C NMR, and mass.

Antidepressants: Current Strategies and Future Opportunities

Recent advances in research on depression have confirmed that it is common, recurrent and disabling mental disorder. Current medication for the treatment of depression have limited efficacy and delayed onset of therapeutic action. In view of the limitation of the current antidepressant pharmaceuticals, tremendous research efforts are ongoing to search for a pharmacological treatment which may improve antidepressive efficacy, onset of action or even both therapeutic parameters. To address these needs, numerous combination therapies that maintain the benefits associated with selective serotonin reuptake inhibitors (SSRIs) but attempts to improve efficacy or reduce side effects by additional mechanism (5-HT₁A, 5-HT₂C) and newer approaches targeting excitatory (glutamate, NMDA, mGluR₂, mGluR₅) or inhibitory aminoacid system (GABA) or peptidergic system(neurokinin1, corticotrophin releasing factor1, melanin concentrating hormone1) have been identified. The goal of this review is to give a brief overview of the major advances in monoamine based treatment strategies and the new emerging approaches in the treatment of depression.

Design, synthesis and SAR exploration of hybrid 4-chlorophenylthiazolyl-s-triazine as potential antimicrobial agents

Two novel series of hybrid class 4-chlorophenylthiazole-s-triazine were synthesized via nucleophilic substitution of 2,4,6-trichloro-1,3,5-triazine with distinguished alkenyl/alkyl/aryl/hetero alkyl–aryl amino and mercapto nucleophiles under nitrogen atmosphere. We identified that the spectrums of antibacterial activity of all tested compounds reveal promising and significant inhibition of gram-positive and gram-negative micro-organisms and the most active compounds, 31d and 32d, were found to be non-toxic in preliminary cytotoxicity assay. We also report that the Molinspiration and Osiris Property Explorer calculations have found a new lead 32d, which binds preferentially to the nuclear receptor to exhibit antibacterial potency.

Synthesis, Docking, In Vitro and In Vivo Antimalarial Activity of Hybrid 4-aminoquinoline-1,3,5-triazine Derivatives Against Wild and Mutant Malaria Parasites.

A new series of hybrid 4‐aminoquinoline–1,3,5‐triazine derivatives was synthesized by a four‐step reaction. Target compounds were screened for in vitro antimalarial activity against chloroquine‐sensitive (3D‐7) and chloroquine‐resistant (RKL‐2) strains of Plasmodium falciparum. Compounds exhibited, by and large, good antimalarial activity against the resistant strain, while two of them, that is 8g and 8a, displayed higher activity against both the strains of P. falciparum. Additionally, docking study was performed on both wild (1J3I.pdb) and quadruple mutant (N51I, C59R, S108 N, I164L, 3QG2.pdb) type pf‐DHFR‐TS to highlight the structural features of hybrid molecules.