13552-11-9Relevant articles and documents
Development of an Amino Acid/Hydroxy Oxime Dual Catalyst System for Highly Stereoselective Direct Asymmetric Aldol Reactions in the Presence of Water
Mridha, Moniruzzaman,Ma, Guangning,Palo-Nieto, Carlos,Afewerki, Samson,Cordova, Armando
, p. 383 - 390 (2016/12/24)
An eco-friendly dual catalyst system for stereoselective aldol reactions in the presence of water is described. It is based on the cooperative action of acyclic amino acids and H-bond donating hydroxy oxime catalysts. The synthetic utility of this dual catalyst system was further demonstrated by applying it as the key step in the expeditious and highly stereoselective total synthesis of d-lyxo-phytosphingosine (29% overall yield). Here the amino acid/hydroxy oxime system significantly accelerated the direct aldol reactions in the presence of water as compared to organic solvents. The stereo- and chemoselectivity were also significantly increased.
Chemo- and Diastereoselective N-Heterocyclic Carbene-Catalyzed Cross-Benzoin Reactions Using N-Boc-α-amino Aldehydes
Haghshenas, Pouyan,Gravel, Michel
supporting information, p. 4518 - 4521 (2016/09/28)
N-Boc-α-amino aldehydes are shown to be excellent partners in cross-benzoin reactions with aliphatic or heteroaromatic aldehydes. The chemoselectivity of the reaction and the facial selectivity on the amino aldehyde allow cross-benzoin products to be obtained in good yields and good diastereomeric ratios. The developed method is utilized as the key step in a concise total synthesis of d-arabino-phytosphingosine.
Total synthesis of d - Lyxo -phytosphingosine and formal synthesis of pachastrissamine via a chiral 1,3-oxazine
Mu, Yu,Kim, Ji-Yeon,Jin, Xiangdan,Park, Seok-Hwi,Joo, Jae-Eun,Ham, Won-Hun
experimental part, p. 2340 - 2346 (2012/09/07)
Concise and efficient syntheses of d-lyxo-phytosphingosine and pachastrissamine were achieved utilizing a chiral oxazine. The key features in these strategies are the stereoselective intramolecular oxazine formation catalyzed by palladium(0), and intermolecular olefin cross-metathesis. Georg Thieme Verlag Stuttgart · New York.
Total syntheses of D -xylo- and D -arabino-phytosphingosine based on the syntheses of chiral 1,3-oxazines
Mu, Yu,Jin, Tian,Kim, Gun-Woo,Kim, Jin-Seok,Kim, Sung-Soo,Tian, Yong-Shou,Oh, Chang-Young,Ham, Won-Hun
experimental part, p. 2614 - 2620 (2012/07/13)
An efficient, stereocontrolled, and short synthetic method for the preparation D-xylo- and D-arabino-phytosphingsine was achieved utilizing chiral oxazines. The key features of this strategy are the stereoselective intramolecular oxazine formation catalyzed by palladium(0) and an intermolecular olefin cross-metathesis reaction.
EFFICIENT METHODS FOR Z- OR CIS-SELECTIVE CROSS-METATHESIS
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Page/Page column 84; 5/6, (2011/09/14)
The present invention generally relates to methods for performing metathesis reactions, including cross-metathesis reactions. Methods described herein exhibit enhanced activity and stereoselectivity, relative to known methods, and are useful in the synthe
Regioselective inversion of the hydroxyl group in d-ribo-phytosphingosine via a cyclic sulfate and bis-sulfonate intermediate
Lee, Yun Mi,Baek, Dong Jae,Lee, Seokwoo,Kim, Deukjoon,Kim, Sanghee
experimental part, p. 408 - 416 (2011/03/20)
The selective synthesis of d-xylo-and d-lyxo-phytosphingosines from commercially available d-ribo-phytosphingosine is described. Thermolysis of the N-carbonyl protected cyclic sulfate led to an inversion of configuration of the proximal hydroxyl group to
Syntheses and biological activities of KRN7000 analogues having aromatic residues in the acyl and backbone chains with varying stereochemistry
Park, Jeong-Ju,Lee, Ji Hyung,Seo, Kyung-Chang,Bricard, Gabriel,Venkataswamy, Manjunatha M.,Porcelli, Steven A.,Chung, Sung-Kee
supporting information; scheme or table, p. 814 - 818 (2010/06/16)
KRN7000 is an important ligand identified for CD1d protein of APC, and KRN7000/CD1d complex can stimulate NKT cells to release a broad range of bioactive cytokines. In an effort to understand the structure-activity relationships, we have carried out synth
Efficient and selective synthesis of D-arabino-, D-lyxo-, and D-xylo-phytosphingosine from D-ribo-phytosphingosine
Kim, Sanghee,Lee, Nakyong,Lee, Sukjin,Lee, Taeho,Yun, Mi Lee
, p. 1379 - 1385 (2008/04/12)
(Chemical Equation Presented) A new high-yield approach to the regio- and stereoselective synthesis of D-arabino-, D-lyxo-, and D-xylo-phytosphingosines from inexpensive D-ribo-phytosphingosine is described. The synthetic methodologies mainly rely on the
Jaspine B (pachastrissamine) and 2-epi-jaspine B: synthesis and structural assignment
Abraham, Elin,Davies, Stephen G.,Roberts, Paul M.,Russell, Angela J.,Thomson, James E.
, p. 1027 - 1047 (2008/09/20)
Jaspine B (pachastrissamine), which was isolated in 2002, is a naturally occurring anhydrophytosphingosine which displays potent biological activity, and as such has attracted much attention from synthetic chemists in recent years, with 14 syntheses reported to date. This review delineates the isolation of jaspine B, and laboratory total syntheses of jaspine B, 2-epi-jaspine B and analogues, which serves to confirm their structure and stereochemistry.
Asymmetric synthesis of N,O,O,O-tetra-acetyl d-lyxo-phytosphingosine, jaspine B (pachastrissamine), 2-epi-jaspine B, and deoxoprosophylline via lithium amide conjugate addition
Abraham, Elin,Brock, E. Anne,Candela-Lena, José I.,Davies, Stephen G.,Georgiou, Matthew,Nicholson, Rebecca L.,Perkins, James H.,Roberts, Paul M.,Russell, Angela J.,Sánchez-Fernández, Elena M.,Scott, Philip M.,Smith, Andrew D.,Thomson, James E.
supporting information; experimental part, p. 1665 - 1673 (2008/10/09)
The highly diastereoselective anti-aminohydroxylation of (E)-γ-tri-iso-propylsilyloxy-α,β-unsaturated esters, via conjugate addition of lithium (S)-N-benzyl-N-(α-methylbenzyl)amide and subsequent in situ enolate oxidation with (+)-(camphorsulfonyl)oxaziri
