Mitsumasa Haruna

Seven guaianolides from Eupatorium chinense

Abstract Two allyl hydroperoxy guaianolide sesquiterpene lactones (peroxyeupahakonin-A and -B) and five new guaianolides (eupahakonin-A and -B, eupahakonenin-A and -B, and eupahakonesin) were isolated from E. chinense and characterized. The allyl hydroperoxy sesquiterpene lactones were characterized by spectral and chemical methods. They were prepared chemically by photosensitized oxygenation of eupahakonin-A.

Alteration of Na+ permeability in human erythrocytes as studied by 23Na-NMR and inhibition of the kidney Na+,K+-ATPase activities with saponins: Interaction of Gleditsia saponins with human erythrocyte membranes

Abstract Interaction of Gleditsia saponin C 1 , bis-monoterpenyl echinocystic acid 3,28-O-bisglycoside, with human erythrocyte membranes and artificial membranes was investigated by means of the hemolytic activities, alteration of Na + permeability by 23 Na-NMR spectroscopy and inhibition of Na + ,K + -ATPase activities. Interaction of Gleditsia saponin C ( 1 ), bis-monoterpenyl echinocystic acid 3,28-O-bisglycoside, with human erythrocyte membranes and artificial membranes was investigated by means of the hemolytic activities, alteration of Na + permeability by 23 Na-NMR spectroscopy and inhibition of Na + ,K + -ATPase activities.

(+)-Arctigenin, a lignan from Wikstroemia indica

Abstract A new lignan, (+)-aretigenin has been isolated from the roots of Wikstroemia indica (Nan-Ling-Jao-Hua) and identified as 8(R) 8′(S)-4′-hydroxy-3, 4,3′-trimethoxylignan-olid (9, 9′) on the basis of spectral evidence as well as a direct comparison with its enantiomer, (−)-arctigenin.

Physical properties of solid dispersion of a nonsteroidal anti-inflammatory drug (M-5011) with Eudragit E.

Some acidic nonsteroidal anti-inflammatory drugs (NSAIDs) are poorly soluble in the stomach. In this study, M-5011, d-2-[4-(3-methyl-2-thienyl) phenyl] propionic acid, was used as a model substance. To increase the dissolution rate of M-5011, a solid dispersion of M-5011 was prepared by the powder mixing method using Eudragit E-100 (aminoacryl methacrylate copolymer) as a carrier. Evaluation by X-ray diffraction and differential scanning calorimetry (DSC) revealed that M-5011 easily formed a solid dispersion with E-100. The dissolution behavior of a physical mixture prepared immediately after mixing and the mixture stored for 14 days at 40°C were examined. It was observed that the former, containing a great deal of E-100, showed a fairly good dissolution behavior, and the latter had a better dissolution rate. The mechanism of the interaction of M-5011 and E-100 was investigated by infrared (IR) spectroscopy and nuclear magnetic resonance (NMR). The interaction was simulated by NMR using a monomer of Eudragit E-100.

Angeloylcumambrin-B, an antimicrobial sesquiterpene lactone from Chrysanthemum ornatum var. Spontaneum

Abstract Angeloylcumambrin-B, a new antimicrobial guaianolide sesquiterpene lactone, was isolated from Chrysanthemum ornatum and the structure was determined by a combination of chemical and physical methods.

Novel total synthesis of (±)-erysotramidine, an oxo-erythrinan alkaloid

A simple synthetic route to (±)-erysotramidine (1), an oxo-erythrinan alkaloid, including the novel ring cleavage of the aza-tricyclo[3.2.0.0] compound (6) with phenylselenyl chloride is reported.

Quantitative analysis of the kinetics of phospholipase A2 using fast atom bombardment mass spectrometry

Fast atom bombardment mass spectrometry that can directly analyze lysophospholipids was used to quantitatively determine the kinetics of phospholipase A2. This method is 1250 times more sensitive than the colorimetric assay.

Regio- and stereo-specific allylic oxidation of germacrane-type sesquiterpene lactones with selenium dioxide and t-butyl hydroperoxide

The regio- and stereo-specific allyic oxidation of the germacrane-type sesquiterpene lactones epitulipinolide (1), eupatoriopicrin acetonide (2), and the O-methanesulphonate (3) with SeO2 and t-butyl hydro-peroxide is discussed.

Three new acridone-coumarin dimers from a Citrus plant

Three new acridone-coumarin dimers, named dioxinoacrimarine-A (1), neo- acrimarine-E (2) and acrimarine-N (3) were isolated from the roots of Citrus plant and their structures were elucidated on the basis of spec- troscopic methods

Design and synthesis of hapten to induce phospholipase A2-like catalytic antibody

Abstract Haptens 1a and 1b , trasition-state analogs inducing phospholipase A 2 -like catalytic antibody, were synthesized. Hapten 1a inhibited hydrolysis of the sn -2 ester of phospholipid.