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The modular synthesis of structurally unique dragocins A—C (1—3) and their analogues, characterized by an uncommon tri-oxa-tricyclic[6.2.1]undecane skeleton and the presence of a heteroatomic substituent at the C-4' position, has been successfully achieved using commercially available and inexpensive anisomycin and D-ribofuranosyl thioglycoside derivative as the starting materials. The construction of the tri-oxa-tricyclic[6.2.1]undecane moiety involved the stereoselective formation of the β-ribofuranosidic bond and DDQ-promoted intramolecular cross-dehydrogenative etherification. Additionally, the equipment of a chlorine atom and a methoxy group at the tertiary C-4' position was accomplished through a silver-catalyzed radical decarboxylative chlorination reaction and an electrophilic etherification reaction of the enol intermediate. The cytotoxicity assessment indicated that demethyl dragocin A (28), the N-demethylated derivative of dragocin A, may serve as a promising anticancer candidate. More details are discussed in the article by Li et al. on pages 1107—1113.