An improved process for the synthesis of prasugrel hydrochloride with an overall yield of 58%, 99.9% purity, and meeting all other quality requirements is described.

An efficient, telescopic, and scalable process for an antihypertensive drug substance, valsartan with an overall yield of 58%, and ∼99.9% purity is described. A simple, and safe process is developed for the recovery of tributyltin chloride from the tributyltin hydroxide, byproduct formed in the tetrazole ring construction, and reused in the synthesis of valsartan.

An improved process has been developed for the active pharmaceutical ingredient, ranolazine with 99.9% purity and 47% overall yield (including three chemical reactions and one recrystallization). Formation and control of all the possible impurities is described. All the solvents used in the process were recovered and reused. The unreacted piperazine is recovered as piperazine monophosphate monohydrate salt.

New and concise synthetic routes have been devised for the regioisomeric and iminium impurities of clopidogrel bisulfate. The synthesis features utilization of commercially available starting materials and simple reactions.

Preparation of some new carbazolyloxy propanolamine derivatives and their cyclization into corresponding oxazolidinonyl/oxazolidinyl carbazole derivatives were described. Introductionß-Adrenergic blocking agents (ß-bIockers) M mostly comprising of ß-amino alcohols are of pharmaceutical significance and have received major attention due to their utility in the management of cardiovascular disorders 1 including hypertension, 6 anginapectoris, cardiac arrhythmias, and other disorders 7 related to the sympathetic nervous system.Aryloxypropanolamine structure is the key pharmacophore in ß-Blockers. 8 Propranolol 3 is the prototype agent for this class of compounds. While propranolol affects βι and ß2 receptors, other drugs such as atenolol 9 and metoprolol 10 have greater affinity for βι receptors and are described as cardioselective. Betaxolol" is the most β, selective of the currently available agents.As a part of our studies towards the synthesis of new drug candidates, we have prepared some new carbazolyloxy propanolamine derivatives and their corresponding cyclised compounds to study their ß-blocking activity. Results and discussionOxirane ring opening in carbazole propyloxy epoxide 1 by using aliphatic and aromatic amines as nucleophiles served as an apt pathway in getting the desired amino alcohols. Required precursor 1 was prepared by a known procedure by condensing 4-hydroxy carbazole with epichlorohydrin. 12 Thus, epoxy compound 1 smoothly provided l-(9//-carbazol-4 yloxy)-3-((4-methoxy phenyl) amino)-propan-2-ol (2a) on reacting with 4-methoxy aniline in refluxing toluene. Several aromatic and aliphatic amines were employed to provide corresponding amino alcohols 2b-l (Table-1).