In the same manner but replacing 4-oxo-4H,5H-[1]benzopyrano[4,3-b]pyran-3-carboxaldehyde with an equivalent amount of another compound of formula VI described in Example 2, the following compounds of formula VII are obtained respectively: 3-hydroxymethyl-4H,5H-[1]benzothiopyrano[4,3-b]-pyran-4-one, mp 147°-149° C., 9-(1-methylpropyl)-3-hydroxymethyl-4H,5H-[1]benzothiopyrano[4,3-b]pyran-4-one, mp 82°-84° C., 9-butyl-3-hydroxymethyl-4H,5H-[1]benzothiopyrano[4,3-b]pyran-4-one, mp 89°-91° C., 5-methyl-3-hydroxymethyl-4H,5H-[1]benzothiopyrano[4,3-b]pyran-4-one, 6-chloro-3-hydroxymethyl-4H,5H-[1]benzopyrano[4,3-b]pyran-4-one, 5-ethyl-17-methyl-3-hydroxymethyl-4H,5H-[1]-benzopyrao[4,3-b]pyran-4-one, 10-ethoxy-5-methyl-3-hydroxymethyl-4H,5H-[ 1]benzothiopyrano[4,3b]pyran-4-one-1,1-dioxide, 5-propyl-8-trifluoromethyl-3-hydroxymethyl-4H,5H-[1]benzopyrano[4,3-b]pyran-4-one, 7-bromo-5-(1-methylethyl)-3-hydroxymethyl-4H,5H-[]benzothiopyrano[4,3-b]pyran-4-one, 8-butoxy-3-hydroxymethyl-4H,5H-[1]benzothiopyrano[4,3-b]pyran-4-one and 5-butyl-9-hexyl-3-hydroxymethyl-4H,5H-[1]benzopyrano[4,3-b]pyran-4-one.
