Masumi Takemoto

The synthesis of optically active pyridyl alcohols from the corresponding racemates by Catharanthus roseus cell cultures

Abstract A novel method for producing optically active pyridyl alcohols 1a-f from the corresponding racemates was developed. When racemic 3-pyridylphenylmethanol 1b is reacted with Catharanthus roseus cell cultures, (−)- 1b is obtained in 96% yield with 100 %ee.

Biocatalytic dediastereomerization of dibenzylbutanolides by plant cell cultures

Abstract A biocatalytic dediastereomerization method, i.e. reactions allowing the transformation of two diastereomers into one diastereomer in quantitative yield, has been developed.

Synthesis of styrenes through the decarboxylation of trans-cinnamic acids by plant cell cultures

Abstract A new method has been developed for the synthesis of styrenes through the decarboxylation of trans-cinnamic acids by plant cell cultures at room temperature. 4-Hydroxy-3-methoxystyrene (2a), 3-nitrostyrene (2d) and furan (2e) were synthesized quantitatively.

An enzyme-catalyzed synthesis of natural α-tocopherol

Abstract The natural α-tocopherol was synthesized by enzyme-catalyzed enantioselective hydrolysis. The unnatural enantiomer as a baby-product was also converted to natural α-tocopherol by racemerization and repeated enzyme-catalyzed hydrolysis.

Enantioselective oxidative coupling of 2-naphthol derivatives catalyzed by Camellia sinensis cell culture

Optically active 1,1′-binaphthyl-2,2′-diols were synthesized by oxidative coupling of 2-naphthols using Camellia sinensis cell culture as a catalytic system.

Deracemization of racemic 4-pyridyl-1-ethanol by Catharanthus roseus cell cultures.

Immobilized cells of Catharanthus roseus synthesized (R)-4-pyridyl-1-ethanol from the corresponding racemate in 100% yield by stereoinversion of the (S)-alcohol in the racemate to the (R)-alcohol. Furthermore, in the reduction of 4-acetylpyridine, we could synthesize both (R) and (S)-4-pyridyl-1-ethanol during a short or a long incubation.

Synthesis of optically active α-phenylpyridylmethanols by immobilized cell cultures of Catharanthus roseus

We have synthesized optically active α-phenylpyridylmethanols by reduction or hydrolysis with calcium alginate immobilized cells of Catharanthus roseus.

Establishment of Camellia sinensis cell culture with high peroxidase activity and oxidative coupling reaction of dibenzylbutanolides

Abstract We succeeded in establishment of Camellia sinensis cell culture with high peroxidase activity. When dibenzylbutanolides ( 1a – c ) were reacted with C. sinensis cell culture, peroxidase-catalyzed oxidative coupling of 1a – c to cyclic products ( 2a – c ) proceeded quantitatively in the absence of foreign hydrogen peroxide as cofactor.

Synthesis of optically active α-phenylpyridylmethanols by Camellia sinensis cell culture

(S)-(+)-α-phenyl-2-pyridylmethanol has analgetic and anticonvul sant activities; however, effective asymmetric synthesis by chemical or biological means has not been reported. We developed a method for producing (S)-(+)-α-phenyl-2-pyridylmethanol in 83% chemical yield with 86% optical yield by the repetitive use of immobilized Camellia sinensis cell culture. The C. sinensis cell culture showed similar capability for asymmetric bioreduction to that of Catharanthus roseus cell culture.

Oxidative cleavage reaction of substituted indoles catalyzed by plant cell cultures

We have developed a novel method for the oxidative cleavage of indole carbon double bonds in the presence of H 2 O 2 using plant cell cultures as peroxidase. The oxidative method has some advantage, as features such as mild reactions, good yields, easy work-up and safety.