197378-99-7Relevant academic research and scientific papers
Synthesis of β-silyl α-amino acids via visible-light-mediated hydrosilylation
Zhang, Yongqiang,Wang, Wei,Wan, Yi,Zhu, Jiajie,Yuan, Qiyang
supporting information, p. 1406 - 1410 (2021/03/29)
An expedient synthesis of β-silyl α-amino acids is reported via the application of visible-light-mediated hydrosilylation. The reaction utilizes readily accessible and structurally diverse hydrosilanes to provide radicals for conjugate addition to dehydroalanine ester and analogues. Notably, the use of chiral methyleneoxazolidinone as the substrate and chiral inducer enabled the highly stereoselective synthesis. Furthermore, the reaction could also be performed in a continuous flow fashion and scaled up to the gram scale.
Syntheses of racemic and non-racemic silicon- and germanium-containing α-amino acids of the formula type H2NCH(CH2ElR3)COOH (El=Si, Ge; R=organyl) and incorporation of D-H2NCH(CH2SiMe3)COOH and D-H2NCH(CH2GeMe3)COOH into biologically active decapeptides: A study on C/Si/Ge bioisosterism
Merget, Markus,Günther, Kurt,Bernd, Michael,Günther, Eckhard,Tacke, Reinhold
, p. 183 - 194 (2007/10/03)
Two novel efficient methods for the synthesis of racemic silicon- and germanium-containing α-amino acids of the formula type rac-H2NCH(CH2ElR3)COOH (El=Si, Ge; R=organyl), starting from 3,6-diethoxy-2,5-dihydropyrazine, have been developed. Racemic α-amino acids synthesized: rac-H2NCH(CH2SiMe3)COOH (rac-2), rac-H2NCH(CH2GeMe3)COOH (rac-3), rac-H2NCH(CH2SiMe2Ph)COOH (rac-4), rac-H2NCH(CH2GeMe2Ph)COOH (rac-5), and rac-H2NCH(CH2SiMe2CH=CH2)COOH (rac-6). Preparative liquid-chromatographic resolution of rac-2 and rac-3 [CHIROBIOTIC T (glycopeptide Teicoplanin covalently linked to spherical silica gel) as the stationary phase] yielded the α-amino acids (R)-2, (S)-2, (R)-3, and (S)-3. The (R)- and (S)-enantiomers of β-(trimethylsilyl)alanine [(R)- and (S)-2] and β-(trimethylgermyl)alanine [(R)- and (S)-3] are sila-analogs and germa-analogs, respectively, of the antipodes of the non-proteinogenic α-amino acid β-tert-butylalanine [(S)- and (R)-H2NCH(CH2CMe3)COOH; (S)- and (R)-1]. Starting from the N-Fmoc-protected C/Si/Ge-analogous (D-configurated) α-amino acids (R)-1, (S)-2, and (S)-3, the C/Si/Ge-analogous decapeptides 7-9 [Ac-D-Nal1-4-Cl-D-Phe2-D-Pal3-Ser 4-N-Me-Tyr5-D-Hci6-Nle7-Arg 8-Pro9-D-Me3El-Ala10-NH2 (7, El=C; 8, El=Si; 9, El=Ge)] were prepared by sequential solid-phase synthesis. The decapeptides 7-9 were studied in vitro in a functional assay using a recombinant cell line expressing the human GnRH receptor (agonist Triptorelin). Compounds 7-9 behaved as medium-potent GnRH antagonists, the antagonistic potencies of these three C/Si/Ge analogs being very similar.
Synthesis of silicon-containing α-amino acids and hydantoins
Smith, Richard J.,Bratovanov, Svetoslav,Bienz, Stefan
, p. 13695 - 13702 (2007/10/03)
Three new silicon containing α-amino acids 6a-c and their respective hydantoin derivatives 8a-c have been prepared in racemic form. Alkylation of an α-amino cyanoacetate derivative with iodomethyl-substituted silanes, followed by hydrolysis gave the amino acids, and the subsequent reactions with KOCN and with HCl gave the hydantoins. The hydantoins are planned to be subjected to a biotechnological deracemization process.
