Synthesis and bronchodilatory activity of some nitrogen bridgehead compounds
Dharam Paul Jindal1, Ravinder Singh Bhatti, Seema Ahlawat
1University Institute of Pharmaceutical Sciences (formerly Department of Pharmaceutical Sciences), Panjab University, Chandigarh 160 014, India. dharampjindal@yahoo.co.in
Abstract:
A series of tricyclic nitrogen bridgehead compounds 7-22 have been synthesised and evaluated for their in vitro bronchodilatory activity using isolated guinea pig tracheal chain, precontracted with acetylcholine. The relaxant effect of 2,3,4,5-tetrahydroazepino[2,1-b]-8,9-dimethoxyquinazolin-11(1H)-one (7) (DPJ-386) was greater than that of theophylline, aminophylline and quinazoline derivative 3, which lacks methoxy groups at positions 8 and 9. Various nitrogen containing functionalities such as benzylamino, acetamido, benzamido and phthalimido were also introduced at 9 position of 3. This resulted in loss of relaxation activity in precontracted guinea pig tracheal chain. These results show that the better relaxation property possessed by compound 7 hydrochloride is due to methoxy groups at 8 and 9 positions.
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