Boron trifluoride, 12% in methanol

5-allyl-5-(sec-butyl)-2-thioxodihydropyriMidine-4,6(1H,5H)-dione

2,3-Dihydro-5-(1-methylpropyl)-5-(2-propenyl)-2-thioxo-4,6(1H,5H)-pyrimidinedione