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Updated: Sep 21, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Synthesis, beta-adrenergic blocking activity and beta-receptor binding affinities of
Dharam Paul Jindal1, Mohane S Coumar, K Nandakumar
1University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh 160014, India. dharampjindal@yahoo.co.in
Abstract:
The compounds 1-isopropylamino-3-(2-isopropyl-5-methyl-phenoxy)-propan-2-ol oxalate (5) and 1-tert-butylamino-3-(2-isopropyl-5-methyl-phenoxy)-propan-2-ol oxalate (6) were synthesized from thymol (1), a naturally occurring agent in Thymus vulgaris L. Pharmacological evaluation of 5 and 6 were carried out using mouse ECG and isolated rat uterus models. Pretreatment of 5 (100 microg/kg, i.v.) and 6 (50 microg/kg, i.v.) antagonized isoprenaline (2 microg/kg, i.v.) induced tachycardia, similar to that of atenolol (CAS 29122-68-7, 20 microg/kg, i.v.) pretreatment in mouse ECG experiments as measured by R-R interval. Pretreatment of 5 and 6 blocked isoprenaline and adrenaline induced relaxation of isolated rat uterus (unprimed). Also the compounds 5 and 6 were subjected to in vitro beta1- and beta2-adrenergic receptor binding assay using turkey erythrocyte membrane (beta1) and lung homogenate of rats (beta2). Both 5 and 6 showed beta-adrenergic receptor affinity comparable with that of propranolol (propranolol hydrochloride, CAS 318-98-9) with out selectivity to any one beta-adrenergic receptor. These results suggest that both the compounds possess non-selective beta-adrenergic blocking activity, with the tert-butyl derivative 6 being more active than the isopropyl derivative 5.
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