1069-31-4Relevant articles and documents
Highly enantioselective synthesis of non-natural aliphatic α-amino acids via asymmetric hydrogenation
Ji, Jianjian,Chen, Caiyou,Cai, Jiayu,Wang, Xinrui,Zhang, Kai,Shi, Liyang,Lv, Hui,Zhang, Xumu
supporting information, p. 7624 - 7627 (2015/07/15)
By employing a rhodium-Duanphos complex as the catalyst, β-alkyl (Z)-N-acetyldehydroamino esters were smoothly hydrogenated in a highly efficient and enantioselective way. Excellent enantioselectivities together with excellent yields were achieved for a series of substrates. An efficient approach for the synthesis of the intermediate of the orally administered anti-diabetic drugs Alogliptin and Linagliptin in the DPP-4 inhibitor class was also developed.
9-BBN: An amino acid protecting group for functionalization of amino acid side chains in organic solvents.
Dent 3rd., William H,Erickson, W Randal,Fields, Stephen C,Parker, Marshall H,Tromiczak, Eric G
, p. 1249 - 1251 (2007/10/03)
9-Borabicyclononane (9-BBN) has been utilized to protect functionalized amino acids for potential chemoselective side chain manipulation. The 9-BBN group imparts organic solubility to otherwise hydrophilic molecules and is tolerant of a wide range of reaction conditions. The high degree of solubility of these molecules in THF is particularly noteworthy. It is cleaved with either aqueous HCl or by exchange with ethylenediamine in methanol. [reaction: see text]
Biosynthesis of blasticidin S from L-α-arginine. Stereochemistry in the arginine-2,3-aminomutase reaction
Prabhakaran,Woo,Yorgey,Gould
, p. 5785 - 5791 (2007/10/02)
A series of labeled α-arginines have been fed to fermentations of Streptomyces griseochromogenes in order to examine the mechanism of L-β-arginine formation in the biosynthesis of the antibiotic blasticidin S. [3-13C,2-15N]Arginine was synthesized and fed; analysis of the derived antibiotic by 13C NMR spectroscopy revealed the retention of the original α-nitrogen and its intramolecular migration to the β-position, revealing the presence of an arginine-2,3-aminomutase. Feedings of [2,3,3-2H3]-, [3,3-2H2]-, and [2-2H]arginines revealed the complete retention of the original β-hydrogens with migration of one to the α-position, as well as partial loss of the original α-hydrogen presumably due to arginine racemase activity. (3R)-[3-2H]- and (3S)-[3-2H]arginines were synthesized unambiguously and used to determine that the pro-3R hydrogen of α-arginine migrates to the α-position (C-2). δ-N-[13CH3]Methylarginine was synthesized, mixed with [guanidino-14C]arginine, and fed to S. griseochromogenes. A 42% incorporation of radioactivity from arginine was obtained, but no 13C enrichment was observed in the blasticidin S sample, indicating that arginine, itself, is the aminomutase substrate.
The biosynthesis of the streptolidine moiety in streptothricin F
Martinkus,Tann,Gould
, p. 3493 - 3505 (2007/10/02)
A series of arginines specifically labeled either with 13C and 15N or with 2H were synthesized and fed to Streptomyces L-1689-23. The streptothricin F isolated in each case was analyzed by either 13C or 2H NMR, respectively, in order to determine the labeling pattern obtained. From these results, it appears that arginine is metabolized to a β-ketoarginine, possibly via a pyridoxal phosphate adduct, and then via cyclization, reduction, rearrangement, and hydroxylation to the streptolidine moiety. The pathway described can also account for the formation of other known antibiotics, and for β-hydroxy-γ-amino acids, generally.
Aminosaeuren, I. Darstellung von Aminosaeuren aus Halogencarbonsaeure-alkylestern mit Alkalimetallcyanaten
Effenberger, Franz,Drauz, Karlheinz,Foerster, Siegfried,Mueller, Wolfgang
, p. 173 - 189 (2007/10/02)
α- and ω-halo- as well as α,ω-dihalocarboxylic alkyl esters react with potassium cyanate in the presence of alcohol at 80 - 120 deg C in dipolar aprotic solvents to yield α- and ω-(alkoxycarbonylamino)- and α,ω-bis(alkoxycarbonylamino)carboxylic alkyl esters, respectively, in good yields.Hydrolytic cleavage of these mono- or diurethanes with an aqueous solution of hydrochloric acid/formic acid leads to the corresponding amino acid hydrochlorides in nearly quantitative yields.
