Masaru Kido

Novel sesquiterpene esters with alkaloid and monoterpene and related compounds from Tripterygium hypoglaucum: A new class of potent anti-HIV agents

Abstract Two new sesquiterpene polyol esters (triptonine A and B) with alkaloid and monoterpene were isolated from Tripterygium hypoglaucum (Levl.) Hutch. Their structures were elucidated by spectroscopic means and X-ray analysis. Triptonine A ( 1 ) and hypoglaunine B 3) ( 4 ) demonstrated potent anti-HIV activity with EC 50 values of 2.54 and 0.13μg/ml and therapeutic index values of 39.4 and >1000, respectively.

Diaryldimethylbutane lignans from Myristica argentea and their antimicrobial action against Streptococcus mutans

Abstract Four 1,4-diaryl-2,3-dimethylbutane type lignans were isolated from the aril of Myristica argentea . In addition to two known lignans, namely erythro -austrobailignan-6 and meso -dihydroguaiaretic acid, two new compounds were determined to be rel -1-(4-hydroxy-3-methoxyphenyl)-4-(3,4-methylenedioxyphenyl)-2,3-dimethylbutan-1-o1 (myristargenol A) and rel -1,4-di(4-hydroxy-3-methoxyphenyl)-2,3-dimethylbutan-1-o1 (myristargenol B) by chemical and spectroscopic methods.

Studies on total syntheses of antitumor styryllactones: Stereoselective total syntheses of (+)-goniofufurone, (+)-goniobutenolide A, and (−)-goniobutenolide B

Abstract A highly stereoselective aldol reaction of the aldehyde 11, derived from (+)-tricarbonyl(η6-2-trimethylsilylbenzaldehyde)chromium(0) complex (4), with 2-trimethysilyloxyfuran afforded the γ-lactone derivative 13. The γ-lactone 13 was subsequently converted into three antitumor styryllactones, (+)-goniofufurone, (+)-goniobutenolide A, and (−)-goniobutenolide B.

Triptoquinone A and B novel interleukin-1 inhibitors from Tripterygium wilfordii var Regeli

Abstract Novel interleukin-1 inhibitors, triptoquinone A (1) and B(2), have been isolated from Tripterygium wilfordii v a r regelli, and their structures were elucidated mainly by spectroscopic methods including X-ray.

Asymmetric aldol reaction: A highly erythro-selective aldol reaction between tricarbonyl(o-trimethylsilylbenzaldehyde derivative )-chromium (0) complexes and cyclic silyl enol ethers

Abstract Reaction of (±)-chromium (0) -complexes 4e-g with 5–7 gave the erythro isomers in a highly selective manner. This aldol reaction was successfully applied to the asymmetric one. The absolute configuration was determined by X-ray analysis of (—)- erythro -8e.

Synthesis of a sulfulr-containing 10-membered enediyne model compound related to the esperamicin/calicheamicin/dynemicin agylcones

Abstract Synthesis of the 10-membered heterocyclic enediyne 4 and its conversion to the benzenoid adduct 10 via the Bergman reaction are described.

An efficient synthesis of pironetins employing a useful chiral building block,(1S,5S,6R)-5-hydroxybicyclo[4.1.0]heptan-2-one

Abstract A convergent total synthesis of pironetin1 and related compound2 using a chiral building block,(1S,5S,6R)-5-hydroxybicyclo[4.1.0]heptan-2-one5 is described. Both the dithiane47 and the epoxide32 with proper substituents were employed as coupling partners to construct the whole carbon skeleton48, which was converted to (−)-pironetin1 and (−)-2 in few steps. The usefulness of5 for polyketide synthesis was demonstrated. Download : Download full-size image

Di- and triterpenoids from Tripterygium hypoglaucum

Abstract The methanol extract of dried root outer bark of Tripterygium hypoglaucum (Levl.) Hutch afforded five new triterpenes: 2,3-seco-2,24-epoxy-D:A-friedoolenane-2, 24-olide-29-oic acid named celastolide, 2,23-dihydroxy-3-methoxy-6-oxo-1,3,5(10), 8-tetraene-24-nor-D:A-friedoolenane-29-oic acid, 2-hydroxy-3-methoxy-6-oxo-1,3,5(10), 8-tetraene-24-nor-D:A-friedoolenane-29-oic acid, 2,3-dihydroxy-1,3,5(10), 8-tetraene-24-nor-D:A-friedoolenane-29-oic acid and 3β,11α-dihydroxy-13(18)-ene-oleanane named triptohypol A, B and C and hypodiol, and two new diterpenes: 3β,14,19-trihydroxy-abieta-8,11,13-triene and 7-oxo-11,13-dihydroxy-19(4-3)-abeo-abieta-3,8,11,13-tetraene-19,18-olide named triptobenzene J and K, and 18 known compounds. Their structures were established on the basis of chemical and spectroscopic studies.

X-ray crystal structure of maltitol (4-O-α-d-glucopyranosyl-d-glucitol

Abstract Maltitol, crystallised from aqueous solution, has m.p. 146.5–147°, [α] d + 106.5° (water), and is orthorhombic with the space group P212121 and Z = 4, and with cell dimensions a = 8.166(5), b = 12.721(9), and c = 13.629(6) A. The molecule shows a fully extended conformation with no intramolecular hydrogen-bonds. All nine hydroxyl groups are involved in intermolecular hydrogen-bond networks and in bifurcated, finite chains. The d -glucopyranosyl moiety has the 4C1 conformation, and the conformation about the C-5–C-6 bond is gauche-gauche. The d -glucitol residue has the bent [ap, Psc, Psc (APP)] conformation. The empirical formula for the solubility in water is C = 119.1 + 1.204 T + 4.137 × 10−2 T2 − 7.137 × 10−4 T3 + 7.978 × 10−6 T4. The thermal properties are as follows: ΔHf = 13.5 kcal.mol−1, and Q = −5.57 kcal.mol−1.

NOVEL AND VERSATILE SYNTHESIS OF PYRROLIDINE TYPE AZASUGARS, DAB-1 AND LAB-1, POTENT GLUCOSIDASE INHIBITORS

Abstract Synthesis of glucosidase inhibitors, DAB-1 (1) and LAB-1 (2) from diethyl tartrate is described. The procedure afforded an epimerizable mixture of diastereomeric intermediates 8 and ent. 8, and opened the door not only to the selective synthesis of DAB-1 and LAB-1 but for giving various related analogs.