L-threo-alpha-D-galacto-Octopyranoside,7,8-trideoxy-6-[[(1-methyl-4-propyl-2-pyrrolidinyl)carbonyl]amino]-1-thio-, 2-(dihydrogen phosphate), (2S-trans)-

DescriptionClindamycin phosphate is a water-soluble ester of the semisynthetic antibiotic produced by a 7 (S)-chloro-substitution of the 7 (R)-hydroxyl group of the parent antibiotic, lincomycin. It is a derivative of lincomycin(a lincosamide). It has primarily bacteriostatic action against Gram-positive aerobes and a wide range of anaerobicbacteria. It is a topical antibiotic used in the treatment of infections. These might include infections of the respiratory tract, septicaemia, peritonitis and bone infections. It is also used to treat moderate to severe acne.

UsesClindamycin phosphate is used topically alone or in conjunction with benzoyl peroxide in the treatment of inflammatory acne vulgaris. In weighing the potential benefits of topical clindamycin therapy, the possibility of serious adverse GI effects associated with the drug should be considered. Therapy of acne vulgaris must be individualized and frequently modified depending on the types of acne lesions which predominate and the response to therapy. Topical anti-infectives, including clindamycin, generally are effective in the treatment of mild to moderate inflammatory acne. However, use of topical anti-infectives as monotherapy may lead to bacterial resistance; this resistance is associated with decreased clinical efficacy.Topical clindamycin is particularly useful when used with benzoyl peroxide or topical retinoids. Results of clinical studies indicate that combination therapy results in a reduction in total lesion counts of 50-70%.

UsesClindamycin 2-phosphate is a a salt of clincamycin, a semi-synthetic lincosamide. The salt is prepared by selective phosphorylation of the 2-hydroxy moiety of the sugar of clindamycin. The introduction of the phosphate affords improved solubility for injectable formulations. Like other members of the lincosamide family, clindamycin 2-phosphate is a broad spectrum antibiotic with activity against anaerobic bacteria and protozoans. Clindamycin acts by binding to the 23S ribosomal subunit, blocking protein synthesis.

General DescriptionClindamycin phosphate (Cleocin Phosphate) is the 2-phosphateester of clindamycin. It exists as a zwitterionic structurethat is very soluble in water. It is intended for parenteral(intravenous or intramuscular) administration for the treatmentof serious infections and instances when oral administrationis not feasible. Solutions of clindamycin phosphateare stable at room temperature for 16 days and for up to 32days when refrigerated.

PreparationPreparation of Clindamycin Phosphate: a solution of 808 mg of the phosphorylated ester in 6 ml of pyridine and 16 ml of acetic acid is stirred at ambient temperature while s5 mg of zinc is rapidly added. The mixture is filtered after one hour and evapo rated to a residue which is heated with stirring at 50°C. for 2 hours with a solvent mixture of 2 ml of acetic acid, and 4 ml of 0.5N sulfuric acid. The mixture is cooled and filtered followed by evaporation of the filtrate in vacuo to a residue, which is chromatographed on a suitable ion-exchange resin, in the acid form, and eluted with 2% ammonium hydroxide. The desired product is obtained as ammonium salt by evaporation of the product fractions. (dec. 212°C)