2-Bromo-a-ergocryptine

The technical aspect of 2-bromo-a-ergocryptine synthesis, including the characterisation and significance of the impurities obtained in the production process, were reviewed. In the continuation new ergolene and ergoline compounds were synthesized and tested for the pharmacological activity. 

Today, 2-bromo-a-ergocryptine (bromocriptine) is the second (after dihydroergotoxine) most extensively used compound from the group of ergot alkaloids. 

Bromocriptine mesilate is 2-bromo-a-ergocryptine methane-sulphonate or 2-bromo-12 -hydroxy-2,-(l-methylethyl)-5 -(2-methylpropyl-5 a-ergotaman-3, 6, 18-trione methanesulphonate or Bromocriptinum (INN). It is the active ingredient in Parlodel dosage forms. 

For the specific rotation of 2-bromo-a-ergocryptine and -inine bases see (11). 

The bromination of peptide alkaloids at position 2 can be smoothly achieved by means of the 3-bromo-6-chloro 2-methylimidazo[ l,2-Z>]pyridazine-bromine complex (33) in methylene chloride solution in particular, the clinically important 2-bromo-a-ergocryptine can be prepared by this method in 75% yield.31... 

The preparation of bromocryptine (2-bromo-a-ergocryptine), by the bromination of pure a-ergocryptine by means of iV-bromosuccinimide, has been described, together with details of 2-bromo-a-ergocryptine methanesulphonate, the clinically useful prolactin inhibitor. ... 

Rucman R., Kovsic, J. and Jurgec, M. (1983) A new synthesis of 2-bromo-a-ergocryptine and related ergot derivatives. II Farmaco, 38,406—410. 

The compounds separated are visualized by uv at 254 and 366 nm, respectively, and by iodine vapour. Rf of bromocriptine is 0.27. The potential by-products yield spots at R 1.5 (2-bromo-a-ergocryptinine), and 0.55 (a-ergocryptine). 2-Bromo-lysergic acid remains at the starting point. 

Stanovnik, B., Tisler, M., Jurgec, M. and Rucman, R. (1981) Bromination of a-ergocryptine and other ergot alkaloids with 3-bromo-6-chloro-2-methylimidazo [1, 2-bjpyridazine-bromine complex as a new brominating agent. Heterocycles, 16,741-745. 

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