... 8.' Condensation Reactions of 4-0xo-4H-[ l]benzopyran-3-carbonitrile Chandrakanta Ghosh* and Nimai Tewari Organic Chemistry Laboratory, Department of Biochemistry, Calcutta University, Calcutta 700019, India Received October 26, 1979 ... J. Org. Chem., Vol. 45, No. ...