Takuzo Komiyama

One‐Pot Synthesis of 2‐Arylthio‐2‐cyclohexenone Derivatives by the Diels–Alder Reaction of 4‐Arylthio‐3‐hydroxy‐2‐pyrones

Abstract The base‐catalyzed Diels–Alder reactions of 4‐arylthio‐3‐hydroxy‐2‐pyrones are reported. Treatment of 4‐arylthio‐3‐hydroxy‐2‐pyrones and dienophiles with triethylamine gave 2‐arylthio‐2‐cyclohexenone derivatives by the Diels–Alder reaction involving a decarboxylation in excellent to reasonable yields.

Asymmetric Synthesis of (-)-Verrucosapyrone A by Biocatalyst and Determination of its Absolute Configuration

An asymmetric synthesis of (-)-verrucosapyrone A was achieved by the use of biocatalyst. Absolute configuration of verrucosapyrone A was also investigated.

Novel synthesis of 4-arylsulfenyl-3-hydroxy-2-pyrone : One pot substitution-rearrangement-cyclization reaction of acetonide protected 4,5-dihydroxy-2-chloroglycidic ester by sodium arylthiolate

Treatment of acetonide protected 4,5-dihydroxy-2-chloroglycidic ester with sodium arylthiolate gave 4-arylsulfenyl-3-hydroxy-2-pyrone in excellent to good yields in one pot.

Synthesis of 4-arylthio-3-hydroxyphthalate by the Diels-Alder reaction of 4-arylthio-3-hydroxy-2-pyrone

Abstract Treatment of 4‐arylthio‐3‐hydroxy‐2‐pyrones with acetylenedicarboxylates gave 4‐arylthio‐3‐hydroxyphthalates by the base‐catalyzed Diels–Alder reaction via a decarboxylation in good yields.

One‐Pot Substitution‐Rearrangement Reaction of 2‐Chloroglycidic Ester: Effective Protocol for the Preparation of 3‐Arylsulfenyl‐2‐keto Ester

Abstract The one‐pot substitution‐rearrangement reaction of 2‐chloroglycidic ester is reported. Treatment of 2‐chloroglycidic ester with sodium arylthiolate at room temperature results in the formation of 3‐arylsulfenyl‐2‐keto ester in excellent to good yields.

Convenient Rearrangement Reaction of 2‐Chloroglycidic Esters by PPh3: A New Synthetic Method of 3‐Chloro‐2‐keto Esters

Abstract A convenient rearrangement reaction of 2‐chloroglycidic esters is reported. Treatment of 2‐chloroglycidic esters with PPh3 under refluxing condition results in the formation of 3‐chloro‐2‐keto esters in good to reasonable yields.

Synthesis of 3-DPA Lactone via Tandem Cyclization Reaction of Acetonide Protected Methyl 4,5-Dihydroxy-2-chloroglycidate

The novel synthesis of 3-DPA lactone, which is known as a potent food intake-control substance, via tandem cyclization reaction of acetonide protected methyl 4,5-dihydroxy-2-chloroglycidate is described.