2-etoxycarbonyl-5,5-dimethylthiolan-3-one 、
3,5-二羟基戊苯 以to produce 1,2-dihydro-2,2-dimethyl-9-hydroxy-7-n-pentyl-4-oxo-4H-thieno-[2,3-c][1] benzopyran in a 72.5% yield, m.p. 203°-206°C.的产率得到1,2-dihydro-2,2-dimethyl-9-hydroxy-7-n-pentyl-4-oxo-4H-thieno-[2,3-c][1]benzopyran