119830-32-9Relevant academic research and scientific papers
2,3-Diaminopropanols obtained from D-serine as intermediates in the synthesis of protected 2,3-L-diaminopropanoic acid (L-DAP) methyl esters
Aiello, Donatella,Athanassopoulos, Constantinos M.,Mazzotti, Fabio,Siciliano, Carlo,Temperini, Andrea,de Luca, Pierantonio
, (2020)
A synthetic strategy for the preparation of two orthogonally protected methyl esters of the non-proteinogenic amino acid 2,3-l-diaminopropanoic acid (l-Dap) was developed. In these structures, the base-labile protecting group 9-fluorenylmethyloxycarbonyl (Fmoc) was paired to the p-toluensulfonyl (tosyl, Ts) or acid-labile tert-butyloxycarbonyl (Boc) moieties. The synthetic approach to protected l-Dap methyl esters uses appropriately masked 2,3-diaminopropanols, which are obtained via reductive amination of an aldehyde prepared from the commercial amino acid Nα-Fmoc-O-tert-butyl-d-serine, used as the starting material. Reductive amination is carried out with primary amines and sulfonamides, and the process is assisted by the Lewis acid Ti(OiPr)4. The required carboxyl group is installed by oxidizing the alcoholic function of 2,3-diaminopropanols bearing the tosyl or benzyl protecting group on the 3-NH2 site. The procedure can easily be applied using the crude product obtained after each step, minimizing the need for chromatographic purifications. Chirality of the carbon atom of the starting d-serine template is preserved throughout all synthetic steps.
Synthesis of novel chiral NiII complexes of dehydroalanine Schiff bases and their reactivity in asymmetric nucleophilic addition reactions. Novel synthesis of (S)-2-carboxypiperazine
Saghiyan, Ashot S.,Stepanyan, Lala A.,Manasyan, Luiza L.,Geolchanyan, Arpine V.,Djamgaryan, Silva M.,Ajvazyan, Hrant R.,Panosyan, Henry A.,Maleev, Viktor I.,Saveleva, Tatiana F.
scheme or table, p. 2638 - 2645 (2011/02/16)
New chiral NiII complexes of Schiff bases of dehydroalanine with modified chiral auxiliaries (S)-2-N-[N′-(3,4-dichlorobenzyl)prolyl] aminobenzophenone (3,4-DCBPB), (S)-2-N-[N′-(3,4-dimethylbenzyl)prolyl] aminobenzophenone (3,4-DMBPB), (S)-2-N-[N′-(2-chlorobenzyl)prolyl] aminobenzophenone (2-CBPB), and (S)-2-N-[N′-(2-fluorobenzyl)prolyl]- aminobenzophenone (2-FBPB) have been synthesized. Asymmetric Michael addition reactions of primary and secondary amines and thiols to the dehydroalanine moieties of the complexes were studied. (S)-2-FBPB was found to be the best chiral auxiliary in terms of both selectivity of the reactions (de ～92-96%) and reactivity of the complexes. A novel synthetic route toward (S)-2-carboxypiperazine was developed based on the auxiliary.
ASYMMERTIC SYNTHESIS OF Β-SUBSTITUTED α-AMINO ACIDS VIA A CHIRAL Ni(II) COMPLEX OF DEHYDROALANINE
Belokon, , Yuri N.,Sagyan, Ashot S.,Djamgaryan, Silva M.,Bakhmutov, Vladimir I.,Belikov, Vasili M.
, p. 5507 - 5514 (2007/10/02)
An efficient approach to the asymmetric synthesis of β-substituted (S)-alanines is describen.The chiral Ni(II) complex of a Schiff base derived from (S)-o-N-(N-benzylpropyl)aminobenzophenone (BBP) and glycine was treated with formaldehyde and sodium methoxide to give a corresponding (R)-serine complex which, in turn, was converted to the chiral Ni(II) dehydroalanine complex.Michael type base catalyzed addition of nucleophiles (including MeOH, Me2NH, PhCH2NH2, imidazole, PhSH, PhCH2SH,, malonic ester and benzylmagnesium chloride) produced a mixture of diastereoisomeric complexes with a 70-90percent excess of S,S (or L,L) isomers over the S,R (or L,D) ones.The cleavage of pure diastereoisomers with aqueous HCl gave, in good yields, β-substituted (S) (or L)-alanines and regenerated the chiral auxiliary (BBP).
