Two types of oil-in-water emulsions consisting of oleic acid-or ethyl oleate-based magnetic fluid as the dispersed phase in water were prepared with casein as the emulsifier, and their characteristics relating to the emulsion stability were investigated. The mean droplet diameter of ethyl oleate- or oleic acid-based magnetic emulsion was 5.0 or 6.4 μm, respectively. Visual observation of sedimentation volume revealed that ethyl oleate-based emulsion was more stable than oleic acid-based emulsion, and this observation was in accord with the experimental results of droplet number of each emulsion. Concerning the rheological properties, oleic acid- or ethyl oleate-based magnetic fluids showed non-Newtonian flow, but the emulsions prepared from both fluids showed Newtonian flow. These results indicate that ethyl oleate-based magnetic emulsion may be superior to oleic acid-based magnetic emulsion as a magnetic drug-carrying material.

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Dearomatization of N, 3-dimethylphthalimide occurs upon irradiation accompanying incorporation of the solvent alcohol in the aromatic ring. The X-ray crystal structure analysis of the product revealed the complete structure of a multi-substituted cyclohexene system. No evidence for formation of the photo-enol in the phthalimide system has been found during the study of the possible course of the photodearomatization.

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Benzylsulfonyldiazomethane can be used for the ring enlargement of cycloalkanones (1) with various ring sizes. The resulting homologated 2-benzylsulfonylcycloalkanones (2) are easily converted to 1-benzylsulfonyl-1-cycloalkenes (4) by bromination followed by cheletropic ring contraction.

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A highly sensitive enzyme immunoassay of 17α-hydroxyprogesterone has been developed. Glucose oxidase was used as a label enzyme and the double antibody solid phase method was adopted to separate the bound and free fractions after the immune reaction. In the assay of enzyme activity, hydrogen peroxide generated from glucose added as substrate was measured by the chemiluminescence reaction using bis (2, 4, 6-trichlorophenyl) oxalate and 8-anilinonaphthalene-1-sulfonic acid. The detection limit of this method is 0.5 pg/tube. The method is applicable to mass screening for congenital adrenal hyperplasia in neonates.

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The configuration at C-23 in 5β-cholestane-3α, 7α, 12α, 23-tetrol, one of the bile alcohols isolated from the bile and feces of patients with cerebrotendinous xanthomatosis, has been determined by X-ray crystallography to be 23R.

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From pigment-producing callus tissues induced from seedlings of Morus alba L., kuwanon J (1), a new Diels-Alder adduct of two prenylchalcone derivatives has been isolated along with chalcomoracin (2), β-sitosterol and stigmast-5-en-3β-ol-7-one.

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New dimeric analogs of intercalative 2-aminodipyrido-[1, 2-a : 3', 2'-d] imidazole (Glu-P-2), a potent muta-carcinogen isolated from a pyrolysate of L-glutamic acid, were synthesized. The high affinity of these compounds to DNA was demonstrated by fluorescence spectroscopic studies and by their effects in raising the melting temperature (T_M) of DNA.

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Studies on secretin receptors of the stomach need an appropriate methodology. Plasma membrane fraction enriched in basolateral membranes was obtained from rat gastric mucosa using differential centrifugation and Percoll density gradient centrifugation. (Na⁺+K⁺)-ATPase, a marker enzyme for basolateral membranes, was enriched 10.5-fold compared with that found in the homogenate. The binding of ¹²⁵I-[Tyr¹] secretin to the basolateral membrane fraction was rapid, reversible and saturable with an equilibrium K_d of 6.4 nM and the binding capacity of 0.6 pmol/mg of protein.

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Bromination of the 7β-benzenesulfinylpropenylaminocephalosporin (1) with NBS followed by treatment with methanol and sodium borate yielded the 7α-methoxylated cephalosporins (4a∼d). Removal of the side chain of the 7β-amino group of 4d was achieved by treating it successively with PCl₅ and Girard T.

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By utilizing anodic oxidation as the key reaction, various olean-12-ene sapogenols were readily converted into olean-11-en-28, 13β-olide, 11α, 12α-epoxy-oleanan-28, 13β-olide, and 13β, 28-epoxy-olean-11-ene derivatives, respectively in high yields. Since previous protection of hydroxyl groups in the starting compounds was not required, the conversion method was directly applied to hederagenin oligoglycosides and corresponding oligoglycosides of olean-11-ene sapogenols, functionalized as above, were successfully synthesized.

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N⁷-Hydroxy-(11a, b) and N⁷-methoxycephalosporins (13a, b) were synthesized from 7-oxocephems (4a, b) via a sequence of reactions involving, as the main steps, oximation [4a, b→5a, b ; 7a, b] and borane reduction [5a, b→6a, b ; 7a, b→8a, b].

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The fatty acid derivatives 3a, b of bacterial cell-wall peptidoglycan peptides related to FK-156 (1) were synthesized and their immunostimulating activities were examined. The new compounds 3a, b showed significant antiinfectious potencies comparable to that of 1 and 3b especially exhibited a potent tumor-suppressive property lacking in 1.

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