“…This oil was treated again with dimethyloxosulfonium methylide under the same conditions. Purification by chromatography on silica gel (benzene-acetone, 10:1) gave l,3-dibenzyl-5-methylcyclothymine 7 as a viscous liquid; yield 0.9 g (58%); ir (Nujol) 1700 and 1660 cm™1 (-CON-CON-); nmr (CDC13) 9.29 (1 H, doublet of doublets, / = 4.5, /' = 6.0 Hz, Hi endo), 9.00 (1 H, triplet, / = 6.0 Hz, H, e,0), 8.73 (3 H, singlet, CH3), 7.31 (1 H, doublets of doublet, / = 4.5, 6.0 Hz, He), 5.29 (2 H, singlet, C6H5CH2), 4.99 (2 H, singlet, C6H5CH2), 2.67 (10 H, singlet, aromatic protons).…”