OBJECTIVEA series of 2-benzylideneaminonaphthothiazoles were designed and synthesized incorporating the lipophilic naphthalene ring to render them more capable of penetrating various biomembranes.

METHODSSchiff bases were synthesized by the reaction of naphtha[1,2-d]thiazol-2-amine with various substituted aromatic aldehydes. 2-(2'-Hydroxy)benzylideneaminonaphthothiazole was converted to its Co(II), Ni(II) and Cu(II) metal complexes upon treatment with metal salts in ethanol. All the compounds were evaluated for their antibacterial activities by paper disc diffusion method with Gram positive Staphylococcus aureus and Staphylococcus epidermidis and Gram negative Escherichia coli and Pseudomonas aeruginosa bacteria. The minimum inhibitory concentrations of all the Schiff bases and metal complexes were determined by agar streak dilution method.

RESULTSAll the compounds moderately inhibited the growth of Gram positive and Gram negative bacteria. In the present study among all Schiff bases 2-(2'-hydroxy)benzylideneaminonaphthothiazole showed maximum inhibitory activity and among metal complexes Cu(II) metal complex was found to be most potent.

CONCLUSIONThe results obtained validate the hypothesis that Schiff bases having substitution with halogens, hydroxyl group and nitro group at phenyl ring are required for the antibacterial activity while methoxy group at different positions in the aromatic ring has minimal role in the inhibitory activity. The results also indicated that the metal complexes are better antibacterial agents as compared to the Schiff bases.

Amines ; chemical synthesis ; pharmacology ; Anti-Bacterial Agents ; chemical synthesis ; chemistry ; pharmacology ; Cobalt ; Copper ; Nickel ; Schiff Bases ; Structure-Activity Relationship ; Thiazoles ; chemical synthesis ; pharmacology

Objective: Schizophrenia is a serious disease characterized by impairment in the perception or expression of reality, leading to occupational and social dysfunction. The use of antipsychotic medication is now universal in the first-line treatment of schizophrenia. This study was undertaken to compare the efficacy of asenapine with a standard atypical antipsychotic, olanzapine in treating this disease. Methods: It was designed as a single blind, randomized, controlled, parallel group, single centre Phase IV trial of a newer atypical antipsychotic, asenapine versus existing standard atypical antipsychotic, olanzapine. Total 80 subjects were enrolled as per eligibility criteria.Each recruited subject received daily treatment with the trial medication (Olanzapine 10 mg or Asenapine 10 mg daily) for duration of 12 weeks. BPRS, CGI-S, CGI-I, Laboratory parameters and compliance was assessed and analyzed. Continuous variables were compared by t test and non-parametric data was analyzed by Mann−Whitney U test and Wilcoxon signed rank test. Likely categorical variables were analyzed by chi-square test or Fisher’s exact test, as appropriate. Results: The duration of schizophrenia at presentation was comparable in both the treatment groups. There was significant reduction of BPRS score between any two visits of each treatment groups. The decline in CGI-S and CGI-I scores was statistically significant (p ＜ 0.001) when compared between visits of any of the both treatment arms.Adherence to treatment was excellent for all patients. Conclusion Newer atypical antipsychotic asenapine is more effective than standard olanzapine in reducing the symptoms of schizophrenia in this study and further larger studies are to be done.