174953-30-1Relevant articles and documents
Expedient synthesis of (-)-(1S, 2R)-allonorcoronamic acid
Hercouet, Alain,Bessieres, Bernard,Le Corre, Maurice
, p. 283 - 284 (1996)
The title amino acid was synthesized in enantiomerically pure form, starting from (S)-(+)-1,2-propanediol 2 in three steps, by condensation of cyclic sulfate 3 with methyl benzylideneglycinate.
Synthesis of (-)-sedinine by allene cyclization and iminium Ion chemistry
Bates, Roderick W.,Lu, Yongna
supporting information; experimental part, p. 3938 - 3941 (2010/11/04)
A synthesis of the sedum alkaloid sedinine has been achieved employing silver(I)-catalyzed allenic hydroxylamine cyclization and ring-closing metathesis to form a bicyclic N,O-acetal. Ring opening of this acetal with a silyl enol ether under Lewis acidic conditions is exclusively trans selective, leading to the natural product after reduction. On the other hand, conversion of the bicyclic N,O-acetal to a semicyclic N,O-acetal results in no stereoselectivity during such a reaction. The contrasting results can be rationalized by consideration of the conformation of the iminium ions.
Combinatorial synthesis of functionalized chiral and doubly chiral ionic liquids and their applications as asymmetric covalent/non-covalent bifunctional organocatalysts
Zhang, Long,Luo, Sanzhong,Mi, Xueling,Liu, Song,Qiao, Yupu,Xu, Hui,Cheng, Jin-Pei
supporting information; experimental part, p. 567 - 576 (2008/10/09)
A facile combinatorial strategy was developed for the construction of libraries of functionalized chiral ionic liquids (FCILs) including doubly chiral ionic liquids and bis-functional chiral ionic liquids. These FCIL libraries have the potential to be use
Relative and absolute configuration of antitumor agent SW-163D
Nakaya, Mino,Oguri, Hiroki,Takahashi, Kosaku,Fukushi, Eri,Watanabe, Kenji,Oikawa, Hideaki
, p. 2969 - 2976 (2008/03/14)
Our interest on engineering non-ribosomal synthetase responsible for SW-163 biosynthesis prompted us to determine the relative and absolute configuration of antitumor cyclic depsipeptide SW-163s. We first isolated and identified SW-163 homologs D, F and G as known compounds UK-63598, UK-65662 and UK-63052, respectively. Both enantiomers of the unusual constitutive amino acid, N-methylnorcoromic acid, were synthesized in chiral forms starting from (R)- and (S)-1,2-propanediol. The hydrolyzate of SW-163D, a major constituent of this family, was converted with Marfey's reagent, 1-fluoro-2,4-dinitrophenyl-5-L- alanine-amide (L-FDAA), and the resulting mixture of amino acid derivatives was subjected to an LC/MS analysis. Compared with authentic samples, the analytical data unambiguously show that SW-163D consisted of L-Ala, D-Ser and (1S, 2S)-N-methylnorcoronamic acid. The remaining stereochemistry of the N-methylcysteine moieties was determined from NOE data.
Propylene glycol cyclic sulfate as a substitute for propylene oxide in reactions with acetylides
Bates, Roderick W.,Maiti, Tushar B.
, p. 633 - 640 (2007/10/03)
Lithium acetylides react cleanly with propylene glycol cyclic sulfate to give, after acidic hydrolysis, homopropargylic alcohols in good yield. The benzyl and TBDPS protecting groups are stable to these conditions, but the THP, TBS, acetal and orthoester groups are not. The readily available (S)-cyclic sulfate gives the (S)-alcohol without loss of stereochemical integrity.
Indolyl-oxazaphosphorine Precursors for Stereoselective Synthesis of Phosphite Triesters and Dithymidinyl Phosphorothioates
Wang, Jian-Chao,Just, George
, p. 8090 - 8097 (2007/10/03)
Several novel chiral indolyl-oxazaphosphorines 7 were synthesized, and their potential as precursors to chiral phosphorothioates was evaluated. Reaction of 7 with a thymidine derivative gave phosphite triester 8 with a large degree of stereoselectivity. Sulfurization with Beaucage's reagent provided phosphorothioate triesters 9. The chiral auxiliary 9b containing a cyano group could be easily removed with aqueous ammonia to form dithymidinyl phosphorothioate in more than 97% diastereomeric excess. The chiral indolyl-oxazaphosphorines 7 are a new class of precursors for stereoselective synthesis of phosphorothioates.
Enantiospecific synthesis of norcoronamic acids
Hercouet, Alain,Godbert, Nicolas,Le Corre, Maurice
, p. 2233 - 2234 (2007/10/03)
The synthesis of enantiomerically pure norcoronamic acids, starting from enantiomerically pure 1,2-propanediols, is described.
A stereoselective synthesis of dinucleotide phosphorothioate triesters through a chiral indol-oxazaphosphorine intermediate
Wang, Jian-Chao,Just, George
, p. 705 - 708 (2007/10/03)
(S)-1-(indol-2-yl)-propan-2-ol was used as a chiral auxiliary to form a dinucleotide phosphorothioate triester in 97% ee.