Synthesis of Schiff bases of naphtha[1,2-d]thiazol-2-amine and metal complexes of 2-(2'-hydroxy)benzylideneaminonaphthothiazole as potential antimicrobial agents

Objective: A series of 2-benzylideneaminonaphthothiazoles were designed and synthesized incorporating the lipo- philic naphthalene ring to render them more capable of penetrating various biomembranes. Methods: Schiff bases were synthe- sized by the reaction of naphtha[1,2-d]thiazol-2-amine with various substituted aromatic aldehydes. 2-(2'-Hydroxy)ben- zylideneaminonaphthothiazole 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 bac- teria. The minimum inhibitory concentrations of all the Schiff bases and metal complexes were determined by agar streak dilution method. Results: All 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. Conclusion: The 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.

Pharmacognostic study and anti-inflammatory activity of Callistemon lanceolatus leaf

Objective:To study detail pharmacognosy and anti-inflammatory activity of Callistemon lanceolatus(C.lanceolatus) leaf.Methods:Leaf sample was studied by organoleptic, macroscopical,microscopical,phytochemical and other WHO recommended methods for standardizations.The methanolic leaf extract of the plant was also screened for antiinflammatory activity on carrageenan-induced paw edema in rat at doses of 200 and 400 mg/kg, orally.The detail pharmacognostic study of the C.lanceolatus leaf was carried out to lay down the standards which could be useful in future experimental studies.Results:C.lanceolatus methanolic leaf extract showed significant(P<0.0S) anti-inflammatory activity at doses of 200 mg/kg and 400 mg/kg.This significant anti-inflammatory of C.lanceolatus methanolic leaf extract at the dose of 400 mg/kg was comparable with diclofenac sodium.Conchuioiis:The pharmacognostic profile of the C.lanceolatus leaf is helpful in standardization for quality,purity and sample identification.The methanolic extract at a dose of 400 mg/kg shows a significant activity in comparison with the standard drug diclofenac sodium(50 mg/kg).

Antidiabetic and hypolipidemic activities of Kigelia pinnata flowers extract in streptozotocin induced diabetic rats

Objective:To evaluate antidiabetic and hypolipidemic activities of Kigelia pinnata rnethanolic(lowers extract in slreplozolocin(STZ) induced diabetic W islar rat.Methods.Rats were made diabetic by a single dose of STZ at 60 mg/kg body weight i.p.The blood glucose level was checked before and 72 h after STZ injection to confirm the development ot diabetes.The flower extract and glibenclamide were administered orally at the doses of 250 and 500 mg/kg body weight for 21 days.Results:Daily oral treatment with the extract and standard drug for 21 days significantly reduced blood glucose,serum cholesterol and triglycerides levels.High density lipoprotein-cholesterol level was found to be improved(P<0.01) as compared to diabetic control group.Conclusions:It is concluded that Kigellia pinnata flowers extract have significant antidiabetic and hypolipidemic effect.