219916-60-6Relevant academic research and scientific papers
Asymmetric conjugate reductions with samarium diiodide: Asymmetric synthesis of (2S,3R)- And (2S,3S)-[2-2H,3-2H]-leucine-(S)- phenylalanine dipeptides and (2S,3R)-[2-2H,3-2H]- phenylalanine methyl ester
Davies, Stephen G.,Rodriguez-Solla, Humberto,Tamayo, Juan A.,Cowley, Andrew R.,Concellon, Carmen,Garner, A. Christopher,Parkes, Alastair L.,Smith, Andrew D.
, p. 1435 - 1447 (2007/10/03)
The highly diastereoselective samarium diiodide and D2O-promoted conjugate reduction of homochiral (E)- and (Z)-benzylidene and isobutylidene diketopiperazines (E)-5,7 and (Z)-6,8 has been demonstrated. This methodology allows the asymmetric synthesis of methyl (2S,3R)-dideuteriophenylalanine 27 in ≥95% de and >98% ee, and (2S,3R)- or (2S,3S)-dideuterioleucine-(S)- phenylalanine dipeptides 37 and 38 in moderate de, 66% and 74% respectively. A mechanism is proposed to account for this process. The Royal Society of Chemistry 2005.
Conjugate additions of organocuprates to a 3-methylene-6-isopropyldiketopiperazine acceptor for the asymmetric synthesis of homochiral α-amino acids
Bull,Davies,Garner,O'Shea
, p. 3281 - 3287 (2007/10/03)
Addition of a range of organocuprates to (S)-N,N′-bis(p-methoxybenzyl)-3-methylene-6-isopropylpiperazine-2, 5-dione 8 affords cis-3-isopropyl-6-alkyldiketopiperazines in excellent yield and >95% de. Subsequent deprotection and hydrolysis of these cis-3-isopropyl-6-alkyldiketopiperazines affords homochiral (S)-α-amino acids in excellent yield.
Stereoselective conjugate addition of organocuprates to a dehydroalanine derived diketopiperazine
Bull, Steven D.,Davies, Stephen G.,O'Shea, Michael D.
, p. 3657 - 3658 (2007/10/03)
An asymmetric synthesis of homochiral α-amino acids has been developed which is based on the conjugate addition of organocuprates to the dehydroalanine equivalent (3S)-N,N′-bis(p-methoxybenzyl)-3-isopropyl-6-methylenepiperazine-2,5-dione 6.
