62U 62u (8S,9R,13R,14S,16R)-21-(furan-2-yl)-13-hydroxy-8,14,19-trimethoxy-16-methyl-4,10,12-trimethylidene-3,20,22-trioxo-2-azabicyclo[16.3.1]docosa-1(21),18-dien-9-yl carbamate 62U