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4,5-Dihydro-1H-2,5-benzoxazocine-1,6(3H)-diones have been synthesized by treatment of tert-butoxycarbonyl (Boc)-protected 1,2-cyclic sulfamidates with phthalic acid derivatives. Protection of one acid hydroxy group and the deprotection of the N-Boc group of the adducts, followed by cyclization, afforded the desired products in high yields. When derivatives of isophthalic acid were used in the synthetic sequence, nine-membered-ring analogues were formed. All the prepared compounds except one are novel.

Novel regiomer of herbarumin I (I) exhibits significant cytotoxic activities against five human cancer cell lines, especially against human colon carcinoma and human breast adenocarcinoma.

The starting adducts are prepared by treatment of cyclic sulfamidates with 2-halophenols following a known procedure.

2,4,5-Trisubstituted imidazoles have been synthesized by treatment of benzil with aldehydes and ammonium acetate in water under reflux in the presence of p-dodecylbenzenesulfonic acid as catalyst. The same reaction using an additional amine affords 1,2,4,5-tetrasubstituted imidazoles. The products are formed in high yields within 4 h under eco-friendly conditions.

L-Proline has been used as an organocatalyst for an efficient synthesis of 1,8-dioxo-octahydroxanthenes by treatment of aldehydes (aromatic, heteroaromatic, and aliphatic) with 5,5-dimethyl-1,3-cyclohexanedione. Three new compounds have been prepared.

The biologically interesting quinoline skeleton is readily available in good to excellent yield and functional groups including halogens remain unaffected.