3-(2-Oxopropyl)-3'-methoxycarbonyl-methyl-3,3'4,4-tetrahydro-9,9',10,10'-tetrahydroxy-7,7'-dimeth oxy-1,1'-dioxo-8,8'-bi-1H-naphtho(2,3-c)pyran 55051-93-9 SC 28763 SC-28763