62882-99-9Relevant articles and documents
Derivatives of 3-Mercaptoindole - Synthesis of a Potent Vasoconstrictor, 3-(2-Imidazolin-2-ylthio)indole (Tinazoline)
Nagarajan, K.,Arya, V. P.,Parthasarathy, T. N.,Shenoy, S. J.,Shah, R. K.,Kulkarni, Y. S.
, p. 672 - 679 (2007/10/02)
Indoles are oxidatively coupled with various cyclic and acyclic thioureas using iodine to give rise to 3-(2-imidazolin-2-ylthio)indole, 1-30, 32 and 36-40.Similar products 33, 34 and 35 are respectively obtained from benzindole, 1,6,6-trimethyl-4,5,6,7-tetrahydroindole and 7-azaindole, while alkylation of 3-mercaptoindole 44 with chlormethyl imidazoline leads to 31.Among the products so obtained, 3-(2-imidazolin-2-ylthio)indole is a potent vasoconstrictor and the hydrochloride salt forms the active ingredient of VarsylR. 3-Mercaptoindole (44) readily obtained by alkali treatment of S-(3-indolyl)isothiourea (36) is converted into amine derivatives 47 and 52 and to the acids 53-55.Acid-catalysed cyclisation of 55 affords the expected thiopyranone (57), as well as the interesting isomeric ketone (58).A mechanism is proposed for this novel rearrangement. 3-Mercaptoindole (44) is also converted to α-methylaminoacid (64) via the hydantoin (63). 3-Mercaptoindole-2-carboxylic acid (65) obtained from 10 is transformed to a variety of methylated derivatives 66-72.The amino acid 75 arising by the action of ethylenimine on 65 is esterified to 76 and cyclised to the condensed thiazepinone (77).
