82267-36-5Relevant articles and documents
SUSTAINED RELEASE DELIVERY SYSTEMS COMPRISING TRACELESS LINKERS
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Page/Page column 152, (2018/11/22)
Described herein are drug delivery systems for delivering biologically active agents comprising primary or secondary amines, or a ring nitrogen atom of an azaheteroaryl ring, pharmaceutically acceptable salts thereof, drug delivery reagents related theret
EPC-synthesis of β-amino acid derivatives through lithiated hydropyrimidines
Seebach, Dieter,Boog, Alois,Schweizer, W. Bernd
, p. 335 - 360 (2007/10/03)
Racemic and enantiopure 2-tert-butyltetrahydropyrimidinones (from pivalaldehyde and 3-aminocarboxylic acids) are converted to Alloc-, Boc-, and Z-protected cyclic imino esters (7-10, Schemes 2-4). These are deprotonated to Li enaminates (K, L). Reactions with electrophiles (prim., sec. alkyl, allyl, benzyl, propargyl halides, aldehydes, imines, enoates) give good yields and are highly diastereoselective (products 11-42, Schemes 5-10). A two-step cleavage (removal of protecting group and hydrolysis) under very mild conditions converts the heterocyclic products to α-branched β-amino acid methyl esters (43-61, Schemes 11-13). The structure of the products is determined by NMR spectroscopy (Figure 1), by chemical correlation (Scheme 14), and by X-ray analysis (Figure 2, 3, 7, Table 1). A structure of the Li enaminates is proposed (Figure 4). Mechanistic models are derived for the reactions occurring with formation of two stereogenic centers with relative topicity like (Figures 5, 6).
Synthesis and Stereochemistry of Hypusine, a New Amino Acid in Bovine Brain
Shiba, Tetsuo,Akiyama, Hitoshi,Umeda, Isao,Okada, Satoshi
, p. 899 - 903 (2007/10/02)
Hypusine, a new basic amino acid occurring in the homogenate of bovine brain tissue, was synthesized to determine the absolute structure.Nα-Benzyloxycarbonyl-L-lysine benzyl ester was coupled with (S)- or (R)-4-benzyloxycarbonylamino-1-bromo-2-butanol derived from L- or D-malic acid, respectively.The products were deprotected by catalytic dehydrogenation.One of the synthetic compounds, i.e., (2S,9R)-2,11-diamino-9-hydroxy-7-azaundecanoic acid, was completely identical with natural hypusine in all respects.