Synthesis and antimicrobial activity of 2-substituted [4-(1,3,4-oxadiazol-2-yl methyl)] phthalazin-1(2H)-one derivatives.

A series of new 2-substituted [4-(1,3,4-oxadiazol-2-yl)methyl]phthalazin-1(2H)-one derivatives 7a-h to 9a-h were designed and synthesized from methyl (4-oxo-3,4-dihydrophthalazin-1-yl)acetate (4), which in was turn prepared from phthalic anhydride. The structure of synthesized new compounds were characterized by spectral data and screened for their antimicrobial activities against various bacteria and fungi strains. Several of these compounds showed antimicrobial activity.

Spectrophotometric determination of pefloxacin mesylate in pharmaceuticals.

A spectrophotometric method is described for assay of pefloxacin mesylate (PFM) in bulk drug and in tablets. The method is based on back extraction of the bromophenol blue dye at pH 5.2 from the dye-drug ion pair followed by measurement of the dye absorbance at 590 nm.

Rapid titrimetric and spectrophotometric methods for salbutamol sulphate in pharmaceuticals using N-bromosuccinimide.

One titrimetric and two spectrophotometric methods which are simple, sensitive and rapid are described for the assay of salbutamol sulphate (SBS) in bulk drug and in tablet dosage forms using N-bromosuccinimide (NBS) and two dyes, rhodamine-B and methylene blue, as reagents. In titrimetry, aqueous solution of salbutamol sulphate is treated with a measured excess of NBS in acetic acid medium and after the oxidation of SBS is complete, the unreacted oxidant is determined iodometrically. Spectrophotometric methods entail addition of a known excess of NBS in acid medium followed by the determination of residual oxidant by reacting with a fixed amount of either rhodamine B and measuring the absorbance at 555 nm (method A) or methylene blue and measuring the absorbance at 665 nm (method B).