Design, synthesis, and evaluation of 4,5,6,7-tetrahydrobenzo[d]thiazole-based novel dual kinase inhibitors of CK2 and GSK3ß.

Casein kinase 2 (CK2) and glycogen synthase kinase-3beta (GSK3ß) are responsible for the phosphorylation of a tumor suppressor protein (PTEN) in a cooperative manner which causes its deactivation. Thus, it is essential to inhibit both kinases simultaneously to prevent PTEN deactivation more efficiently. In this study, we have designed a novel lead from Hit15 which was identified in silico as a dual kinase inhibitor against CK2 and GSK3ß through our previous study. The dataset of structural analogs of the lead was designed and confirmed by pharmacophore mapping and molecular docking. The screened analogs were considered further and a series of "tetrahydrobenzo[d]thiazoles" were synthesized. Compound 1g has shown highest dual kinase inhibitory activity at a concentration of 1.9 µM against CK2 and 0.67 µM against GSK3ß. Our results suggest that the presence of a carboxyl group at the meta position of the phenyl ring plays a vital role in dual kinase inhibition.

Impact of Ternary Solvent System in Stability-Indicating Assay Method of Bambuterol: Design of Experiments Approach.

High-performance liquid chromatography method for anti-asthmatic ß2-agonist drug bambuterol, its process-related impurities and its major degradation products was developed and validated using quality by design concept. A 3(3) full factorial design was employed to study the effect of three independent factors, namely, ratio of organic modifiers in mobile phase, pH of the buffer and flow rate of the mobile phase. The responses considered were retention time of the last peak and resolution of poorly separated peaks (drug and PR-4 and drug and DP-3). The optimum conditions for separation were determined with the aid of design of experiments. The optimized ternary solvent composition was a mixture of 10 mM ammonium acetate buffer (pH 6.0), methanol and acetonitrile in the ratio of 90:5: 5 (v/v/v) in solvent reservoir A and 10:45:45 (v/v/v) in solvent reservoir B. The separation of the analytes was achieved by using a gradient method. The predictability criteria of the optimized method demonstrated good correlation between observed and predicted response. The method was validated for specificity, linearity, accuracy, precision and robustness in compliance with the International Conference on Harmonization guidelines Q2R1.

Novel thiazole-thiophene conjugates as adenosine receptor antagonists: synthesis, biological evaluation and docking studies.

Here we report novel thiazole-thiophene conjugates as adenosine receptor antagonists. All the molecules were evaluated for their binding affinity for adenosine receptors. Most of the molecules were found to interact with the A1, A2A and A3 adenosine receptor subtypes with good affinity values. The most potent and selective compound 8n showed an A3Ki value of 0.33µM with selectivity ratios of >90 versus the A1 and >30 versus the A2 subtypes. For compound 8n docking studies into the binding site of the A3 adenosine receptor are provided to visualize its binding mode.

Synthesis, Antiinflammatory and HIV-1 Integrase Inhibitory Activities of 1,2-Bis[5-thiazolyl]ethane-1,2-dione Derivatives.

Based on principles of pharmacophore delineation and drug designing, compounds containing diketofunctionallity namely 1,2-bis[5-thiazolyl]ethane-1,2-diones were designed and synthesized as antiinflammatory agents. The compounds were evaluated in carrageenan-induced rat-paw edema method. G-3, G-6, G-17, G-20, G-23, G-22, L-708 and 906 showed good antiinflammatory activity. In addition as diketo functionality containing compounds are reported to have HIV-1 integrase inhibitory property, and these compounds contains diketo functionality, so these compounds were screened in assay for HIV-1 integrase inhibition. Few compounds showed weak HIV-1 integrase Inhibitory activity.

2-Amino-5-thiazolyl motif: a novel scaffold for designing anti-inflammatory agents of diverse structures.

Substituted thiazoles with different structural features were synthesized and screened for their anti-inflammatory activity in acute carrageenin induced rat paw edema model and chronic formalin induced rat paw edema model. The compounds 1-5 showed 83, 30, 63, 69 and 73% protection, respectively, in acute carrageenin induced rat paw edema model. In 5-day chronic formalin induced rat paw edema model on the fifth day 1 and 5 gave 66 and 41% protection. Both studies were carried out at a dose of 100mg/kg body weight. The activity was compared with that of Ibuprofen, Rofecoxib, and Dexamethasone both in acute and chronic anti-inflammatory models. Compound 1 without COX-1 and COX-2 inhibitory activity showed good activity profile almost mimicking the gold standard Dexamethasone in terms of efficacy. A 7-day study in rats at dose of 100mg/kg showed that this compound does not have any ulcerogenic activity and toxicity. The activity of 5 shows that incorporating two pharmacophoric features in one molecule can be a good drug designing strategy. 2,4-Diaminothiazoles with an aliphatic oxime esters attached via a ketone bridge to the 5th position of thiazole was identified as a novel scaffold for designing anti-inflammatory agents.

Design, synthesis, and SAR studies of some 5-aliphatic oximino esters of thiophene as potential anti-inflammatory leads: comparative biological activity profile of aliphatic oximes vs aromatic oximes.

A series of novel tetra substituted thiophenes were synthesized, characterized, and evaluated for their anti-inflammatory activity in carrageenin induced rat paw edema model-an acute in vivo model. Compounds V1, V3, V11, V12, V17, and V18 showed good anti-inflammatory activity, indicating the importance of oxime moiety in modulating the activity. The structure-activity relationship studies explore "the aliphatic oxime esters" attached via a ketone bridge to fifth position of the thiophene, and indicate that this feature may enhance the anti-inflammatory activity as compared to aromatic oximes. Since free radicals are implicated in various inflammatory disorders, the free radical scavenging activity of some of the synthesized candidates was assessed using 1,1-diphenyl-2-picryl hydrazyl assay. The oxime containing analogs exhibited weak to moderate activity as free radical scavengers in DPPH assay. A plausible reasoning for its free radical scavenging ability is discussed. All the compounds were also screened in nitro blue tetrazolium model, to assess them as superoxide anion radical scavengers. A direct correlation between anti-inflammatory activity and free radical scavenging activity was not seen. The results disclose a new class of anti-inflammatory agents designed and synthesized for the first time wherein the utility of aliphatic oxime esters in modulating the anti-inflammatory activity profile is apparent. This will give us potential anti-inflammatory leads.

Nitroimidazoles, Part XXIII--activity of satranidazole series against anaerobic infections.

A large number of nitroimidazoles have been examined for in vitro activity against three anaerobes - Bacteroides fragilis (Bf), a strain of Bf resistant to metronidazole (16a) and Clostridium perfringens and many found to be active. Among these may be mentioned 1-methyl-5-nitroimidazoles carrying N - bound hetetocycles at position 2, such as satranidazole 1a, 1b, 1c, 1k, 1n and 1v which are at least twice as active as metronidazole (16a), ornidazole (16b) and tinidazole (16c). Even more active are 5-nitroimidazolyl benzimidazole 5d, -thiazolidinone 6b and thiadiazolidine dioxide 8a. Many other types of compounds derived from 1-methyl-2-amino-5-nitroimidazole are feebly active. Among 5-nitroimidazoles with a carbon substituent at position 2, 16a, 16b and 16c are equiactive while dimetridazole 14f is more active than 16a against Bf. Some 2-vinyl derivatives are very potent, with 18f and 18i being outstanding. Activity better than that of metronidazole is seen for nitroimidazooxazepines, e.g. 29d. 5-Nitroimidazoles are more active against anaerobes than 4-nitro isomers. Antianaerobic and antiamoebic activities generally run parallel in these classes of compounds. The study has led to the elaboration of the antianaerobic profile of satranidazole 1a.