Triterpenoid chemistry. XII. Homo-favorskii rearrangement in triterpenoid series.
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چکیده
منابع مشابه
Stereocontrolled synthesis of kelsoene by the homo-favorskii rearrangement.
[reaction: see text] (+/-)-Kelsoene (4) has been synthesized from 2,5-dihydroanisole in 16 steps in 12.5% overall yield. The key step involves a base-catalyzed reaction of gamma-keto tosylate (5), which effects a homo-Favorskii rearrangement to 16 as well as the corresponding intramolecular S(N)2 product 15 from the enolate of 5. Ketone 15 can efficiently be isomerized to cyclobutanone 17 havin...
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We and other studies have elucidated single molecules that can attenuate aging and extend longevity. Indeed, these molecules could prevent age-associated diseases simultaneously and probably extending healthy-life spans. In this review, we discuss recent advances, controversies, opportunities and challenges surrounding ursolic acid (UA) in relationship with aging. In this regard, UA also known ...
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From the roots of Adina rubella, four new quinovic acid glycosides, quinovic acid 3-O-beta-D-glucopyranosyl(1-->4)-beta-D-fucopyranoside, quinovic acid 3-O-beta-D-glucopyranosyl(1-->4)-beta-D-fucopyranosyl-(28-->1)-beta-D- glucopyranosyl ester, quinovic acid 3-O-beta-D-glucopyranosyl(1-->4)-alpha-L-rhamnopyranosyl-(28-->1) -beta-D-glucopyranosyl ester and quinovic acid 3-O-beta-D-glucopyranosyl...
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ژورنال
عنوان ژورنال: Chemical and Pharmaceutical Bulletin
سال: 1975
ISSN: 0009-2363,1347-5223
DOI: 10.1248/cpb.23.1775