53317-08-1Relevant articles and documents
PEPTIDE TURN MIMETICS
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Page/Page column 20, (2011/04/14)
Peptide mimetics of structure X herein which (i) provide a wide range of sidechain functions at all sidechain positions, (ii) can be incorporated in a peptide sequence, (iii) can be readily synthesized and (iv) have a variety of conformations. There is also provided a novel process which can provide valuable intermediates in relation to production of peptide mimetics of structure X which intermediates have a high degree of chemo- and stereo-selectivity. Preferred mimetics include structures I, II, III, IV, V and VI.
Radical allylation, vinylation, alkynylation, and phenylation reactions of α-halo carbonyl compounds with organoboron, organogallium, and organoindium reagents
Takami, Kazuaki,Usugi, Shin-Ichi,Yorimitsu, Hideki,Oshima, Koichiro
, p. 824 - 839 (2007/10/03)
Allylic gallium and indium reagents are found to mediate radical allylation reactions of α-iodo or α-bromo carbonyl compounds. Treatment of benzyl bromoacetate with allylgallium, prepared from allylmagnesium chloride and gallium trichloride, in the presence of triethylborane provided benzyl 4-pentenoate in excellent yield. Addition of water as a co-solvent improved the yields of allylated products. Allylic indium reagents are also useful and can replace the gallium reagents. A diallylborane reagent can allylate an α-iodo ester in good yield. Alkenylation reactions of α-halo carbonyl compounds with alkenylindium proceeded via a radical process in the presence of triethylborane. Unactivated alkene moieties and styryl groups were introduced by this method. The carbon-carbon double bond geometry of the alkenylindiums was retained during the alkenylation. Preparation of an alkenylindium via a hydroindation of 1-alkyne and subsequent radical alkenylation established an efficient one-pot strategy. Radical alkynylations and phenylations with organoindium reagents are disclosed herein.
