The total synthesis of 7-deoxy-6-O-methylfusarentin (1) and a formal synthesis of 7-deoxy-6,8-O-dimethylfusarentin (2) has been successfully achieved in 10 steps. The described tactic underscores a diastereoselective strategy which incorporates a single acyclic reaction based on the initial stereocenter by means of a 1,3-chelation-controlled Reetz-Keck-type allylation.

a b s t r a c tThe concise synthesis of (±)-tetramethoxy-sinensigenin A (2) is reported. The key C-C bond formation, which forged the [3.2.1]-bicyclic ether moiety, was the result of a regio-and diastereoselective intramolecular Marson-type cyclization via a pendent oxocarbenium cation intermediate.

The total syntheses of both (-)-cryptocaryolone and (-)-cryptocaryolone diacetate is presented herein. The usage of a diastereoselective oxy-Michael addition/benzylidene acetal formation coupled with a selective axial oxocarbenium allylation allowed for the preparation of the α-C-glycoside moiety present in the bicyclic bridged structure. In addition, the syn-1,3-diol of the linear portion was installed via a Wacker oxidation followed by a subsequent directed reduction of the appropriate homoallylic alcohol precursor.

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TiCl 4 Mediated Preparation of (E)-Non-conjugated Homoallylic Alcohols with α-Substituted Allylsilanes. -(ALBURY, A. M. M.; JENNINGS*, M. P.; Tetrahedron Lett. 54 (2013) 33, 4487-4490, http://dx.