Trost, Barry M. published the artcileA short and concise asymmetric synthesis of hamigeran B, Synthetic Route of 725251-81-0, the publication is Chemistry – A European Journal (2005), 11(3), 951-959, database is CAplus and MEDLINE.
The interesting biol. properties of the hamigerans wherein hamigeran B (I) is a potent antiviral agent with low cytotoxicity to host cells make these deceptively simple looking structures challenging synthetic targets. A strategy to hamigeran B evolved wherein the three contiguous stereocenters are established ultimately from a Pd catalyzed asym. allylic alkylation (AAA). The latter involves an asym. allylation of a non-stabilized ketone enolate in 77% yield and 93% ee. By using this process, (S)-5-allyl-2-isopropyl-5-methyl-1-trifluoromethanesulfonyloxycyclopentene becomes available in four steps from 2-methylcyclopentanone. Introduction of the aryl unit by cross-coupling proceeded intermolecularly but failed intramolecularly. On the other hand, reductive removal of the triflate permitted a Heck reaction to effect intramol. introduction of the aryl ring. The unusual conformational properties of this mol. architecture are revealed by the regioselectivity of the β-hydrogen elimination in the Heck reaction and the diastereoselectivity of the reduction establishing the stereochem. of the carbon bearing the iso-Pr group. The successful route consists of 15 steps from 2-methylcyclopentanone and dimethylorcinol illustrating the efficiency of the route based upon the Pd AAA.
Chemistry – A European Journal published new progress about 725251-81-0. 725251-81-0 belongs to ethers-buliding-blocks, auxiliary class Boronic acid and ester,Benzene,Ether,Boronic Acids,Boronic acid and ester, name is (3-Methoxy-5-methylphenyl)boronic acid, and the molecular formula is C9H12O, Synthetic Route of 725251-81-0.
Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem