Regioselective C–H alkenylation of imidazoles and its application to the synthesis of unsymmetrically substituted benzimidazoles
作者:Hyeongwoo Kim、Ye Ji Hwang、Inhyuk Han、Jung Min Joo
DOI:10.1039/c8cc02405g
日期:——
A palladium-catalyzed C–H alkenylation of imidazoles has been developed. High C5 selectivity was achieved for C2-unsubstituted and C2-substituted imidazoles usingoxygen and copper(II) acetate, respectively, as oxidants. The obtained products were applied to benzannulation through a sequence involving transposition of N-alkyl groups to give C4-alkenyl imidazoles, alkenylation, thermal 6π-electrocyclization
Sarcodictyin A and Sarcodictyin B, Novel Diterpenoidic Alcohols Esterified by (E)-N(1)-Methylurocanic Acid. Isolation from the Mediterranean StoloniferSarcodictyon roseum
The Mediterranean stolonifer Sarcodictyon roseum (= Rolandia rosea) (Cnidaria, Anthozoa, Alcyonaria, Stolonifera, Clavulariidae) is shown to contain two novelditerpenoidicalcoholsesterified by (E)-N(1)-methyl-urocanic acid (= E)-3-(l-methyl-lH-imidazol-4-yl)acrylic acid). They are sarcodictyin A ( = (−)-(4R,4a,R, 7R,10S,11S,12aR,lZ,5E,8Z)-7,10-epoxy-3,4,4a,7,10,11,12,12a-octahydro-7-hydroxy-6-(methoxycarbonyl)-1
Compounds of formula (I):
are inhibitors of the enzyme Lp-PLA
2
and are of use in therapy, in particular for treating atherosclerosis. In Formula I R
1
, R
2
, R
3
, R
4
, R
5
, R
6
, X and Y are as defined herein.