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Ten new (+)-hydroxybutanolides, linderanolides A-E and isolinderanolides A-E, along with one known one have been isolated from the leaves of Lindera glauca. On the basis of spectroscopic methods and chemical evidence, linderanolides A-E were shown to be (3R,2Z)-3-hydroxy-4-methylenebutanolides having 2-((11E)-11-tetradecenylidene), 2-tetradecylidene, 2-((7Z,10Z)-7,10-hexadecadienylidene), 2-((7Z)-7-hexadecenylidene) and 2-hexadecylidene side-chains, respectively, while isolinderanolides A-E were their corresponding (2E)-isomers.

Three new compounds, along with four known ones, have been isolated from the seeds of Iris pallasii . On the basis of spectroscopic methods and chemical evidence, the new compounds were shown to be 2-[(Z)-10-heptadecenyl]-4,6-dimethoxyphenol, 3,5-dimethoxy-[(Z)-10-heptadecenyl]benzene and 9,9b-di[(Z)-10-heptadecenyl]-4a,8-dihydroxy-2,7-dimethoxy-1,4-dioxo-1,4,4a,9b-tetrahydrodibenzofuran. The biogenetic relationships between these compounds are also discussed.

Four new enediones, belamcandones A-D, have been isolated from the seeds of Belamcanda chinensis . On the basis of spectroscopic methods and chemical evidence, they are concluded to be 4a,8-dihydroxy-2,7-dimethoxy-1,4-dioxo-1,4,4a,9b- tetrahydrodibenzofurans having two alkyl side-chains at the C-9 and C-9b positions.

Eight tetracyclic spirotriterpene derivatives, iristectorones A-H, have been found in the seeds of Iris tectorum . Their structures were established to be the Diels-Alder products of 2-methoxy-6-[( Z )-10-pentadecenyl]- p -benzoquinone with triterpenic conjugated trienes having spiro [4.5] decane skeleton derived from iristectorenes A-H, respectively, on the basis of spectral methods and chemical transformations. A possible biogenetic route for these esters has been also discussed.

Six new triterpene esters, iristectorenes A and C-G, along with one known one have been found in the seeds of Iris tectorum . On the basis of spectroscopic methods and chemical evidence, the esters were established to be 3-{3-hydroxy-2-[5-hydroxy-4,8,12-trimethyl-(3 E ,7 E )-3,7,1 1-tridecatrienyl]-2,3-dimethyl-6-(1-methyl-2-oxoethylidene)-cyclohexyl}propyl ( Z )-9-tetradecenoate,( Z )-11-hexadecenoate, ( Z,Z )-9,12-octadecadienoate, hexadecanoate, ( Z )-11-octadecenoate and octadecanoate, respectively.

The Lewis acid mediated reactions of allenylstannanes 1 and 13 gave trans cyclic ethers 3a and 14, respectively, with high stereoselectivities. The cyclization fo 7 gave trans cyclic ether 9a. The treatment of propargylstannanes 2 and 8 with Lewis acids such as SnCl4, BuSnCl3, and ZnCl2·OEt2 induced isomerization to allenylmetal species, which underwent cyclization to the corresponding 6- and 5-membered cyclic ethers 3 and 9, respectively. The stereoselectivities depended upon the ring size and Lewis acid utilized.

Treatment of 2-vinylbicyclo[3.2.1]oct-6-en-2-ols with KH in toluene gave mainly [5-5] fused-ring compounds through a [1,3] sigmatropic shift.

The aromatic oxy-Cope rearrangement including a benzene ring took place when 1-methoxy-2-aryl-bicyclo[2.2.2]oct-5-en-2- exo -ols and 2-(2-methoxyphenyl)-bicyclo[2.2.2]oct-5-en- exo -2-ols were treated with KH in THF.

The anionic [1,3] rearrangement of both stereoisomeric bicyclo[3.2.1]oct-6-en-2-ols by treatment with KN(TMS) 2 in toluene or in diglyme took place as a stereoconvergent route giving each of the stereoisomeric hydroxydiquinanes.

The synthesis of unique diquinanes, possessing four continuous methyl groups on the convex of the diquinane skeleton, has been achieved by employing a combination of pinacol-type rearrangement and efficient anionic [1,3] rearrangement strategies.

An efficient one-pot synthesis of a 10,10-ethylenebicyclo[5.2.1]dec-8-en-4-one derivative, which can be considered as a synthetic intermediate for the taxane skeleton, has been achieved by tandem anionic [1,3] and oxy-Cope rearrangements of 2-vinylbicyclo[3.2.1] oct-6-en-2-ol.

Two (-)-methoxybutanolides have been isolated from the rhizomes of Lindera glauca . On the basis of spectroscopic methods, their structures were elucidated to be (3 S ,2 E )-2-(11-dodecenylidene)-3-methoxy-4-methylenebutanolide and (3 S ,2 E )-2-(11 -dodecynylidene)-3-methoxy-4-methylenebutanolide, respectively.

Two malate dehydrogenases (MDH-M1 and MDH-M2) were found in a methanol-using yeast, Candida sp. N-16. MDH-M2 was induced with methanol. These enzymes were purified as electrophoretically and isoelectrophoretically homogeneous proteins. The molecular weights of MDH-M1 and MDH-M2 were estimated to be about 78,000 (homodimer) and 160,000 (homotetramer). Several kinetic properties were significantly different between the two enzymes. The value (2.07) of Vmax(oxaloacetate)/Vmax(malate) and Kcats (555 s(-1) for oxaloacetate, 481 s(-1) for NADH) of MDH-M2 were higher than the ratio (1.37) of Vmax and Kcats (241 s(-1) for oxaloacetate, 271 s(-1) for NADH) of MDH-M1, respectively. The activity of MDH-M2 was inhibited by a high concentration of NAD+ and the activity of MDH-M1 by oxaloacetate.