189246-60-4Relevant academic research and scientific papers
Use of heterocycles as chiral ligands and auxiliaries in asymmetric syntheses of sphingosine, sphingofungins B and F
Kobayashi, Shu,Furuta, Takayuki
, p. 10275 - 10294 (2007/10/03)
D-erythro-Sphingosine and its derivatives (dihydrosphingosine, cissphingosine, etc.), sphingofungins B and F have been synthesized from simple achiral compounds using heterocyclic compounds as key chiral ligands and auxiliaries. 5-Benzyloxy-4-ethynyl-2,2-dimethyl-1,3-dioxane (5 or 5- ent), a key intermediate for the synthesis of sphingosine family, was prepared from 1-trimethylsilylpropinal and ketene silyl acetal 4 using a Sn(OTf)2-chiral ligand 1 or 1-ent-catalyzed asymmetric aldol reaction. Sphingosine and its derivatives were readily prepared from 5 according to standard transformation. The chiral hydrophobic side chain (6) of sphingofungin B was synthesized using a catalytic asymmetric aldol reaction using chiral ligand 1-ent. Another key step in the total synthesis of sphingofungin B was a condensation of chiral aldehyde 7 and chiral heterocycle 2. Similarly, the reaction of chiral aldehyde 8 with heterocycle 3 was a key step for the synthesis of sphingofungin F. Highly diastereoselective reactions proceeded smoothly in both cases to afford the corresponding adducts in high yields.
Catalytic asymmetric syntheses of antifungal sphingofungins and their biological activity as potent inhibitors of serine palmitoyltransferase (SPT)
Kobayashi, Shu
, p. 908 - 919 (2007/10/03)
Unambiguous synthetic routes to sphingofungins B and F and to their stereoisomers have been developed based on the tin(II)-catalyzed asymmetric aldol reaction (Chiral Lewis Acid-Controlled Synthesis (CLAC Synthesis)). Efficient enantioselective synthesis using a catalytic amount of a chiral source as well as the effectiveness of this strategy for the synthesis of the sphingofungin family have been successfully demonstrated. Using the stereoisomers of sphingofungin B synthesized, the relevance of its stereochemistry to its SPT inhibitory activity has been revealed.
The Asymmetric Synthesis of Sphingofungin F and the Determination of Its Stereochemistry
Kobayashi, Sh?,Matsumura, Masae,Furuta, Takayuki,Hayashi, Takaomi,Iwamoto, Shunsuke
, p. 301 - 303 (2007/10/03)
The asymmetric synthesis of sphingofungin F has been achieved and its stereochemistry has been determined. Its structure, including the absolute configuration of the chiral centers, was found to be similar to that of sphingofungin B or myriocin. The synth
