title: Syntheses of pterocarpenes and coumestans via regioselective cyclodehydration.
abstract: A highly efficient synthetic route to pterocarpenes and coumestans is described. BCl3-mediated dehydrative cyclization of 1,3-diaryloxyacetones under mild conditions permitted regioselective ring closure to afford 3-((2-iodoaryloxy)methyl)benzofurans which were converted to the corresponding pterocarpenes by Pd-catalyzed intramolecular direct arylation. The subsequent benzylic oxidation led to coumestans. This sequence was applied to the formal syntheses of coumestrol and the proposed structure of plicadin as well as total syntheses of flemichapparins B and C.
authors: College of Pharmacy and Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon, 21983, Republic of Korea. ikyonkim@yonsei.ac.kr.
authors: Maloy
authors: M
authors: Nayak
authors: Youngeun
authors: Y
authors: Jung
authors: Ikyon
authors: I
authors: Kim
mesh_terms: D001572:Benzofurans / Q000138:chemical synthesis* / Q000737:chemistry*; D060326:Chemistry Techniques, Synthetic; D003374:Coumarins / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D001572:Benzofurans; D003374:Coumarins; C505898:coumestan