134313-74-9 ATCC 20928 factor B L 671,776 L 671776 L-671,776 L-671776 Spiro(benzofuran-2(3H),1'(2'H)-naphthalene)-5-carboxaldehyde, 3',4',4'a,5',6',7',8',8'a-octahydro-4,6'-dihydroxy-6-(hydroxymethyl)-2',5',5',8'a-tetramethyl-