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Updated: Jul 9, 2026

In vitro Measurements of Tracheal Constriction Using Mice
Published on: June 25, 2012
SAR studies of capsazepinoid bronchodilators. Part 2: Chlorination and catechol replacement in the A-ring
Magnus Berglund1, María F Dalence-Guzmán, Staffan Skogvall
1Division of Organic Chemistry, Lund University, PO Box 124, SE-221 00 Lund, Sweden.
Abstract:
Capsazepine as well as its derivatives and analogues are general inhibitors of constriction of human small airways. From a systematic variation of the capsazepine structure, divided into four regions, SARs were established. This paper concerns the chlorination of the A-ring as well as the replacement of the catechol with bioisosteric groups. It is revealed that chlorination of the A-ring has a profound effect on activity. Moreover, di-chlorination of the 6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline structure results in a 10-fold increase in potency compared to capsazepine.
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