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We have synthesized α-(phosphoryl)methyl tetrazolyl sulfoxides and examined the reactivities in the thermolyses and in the presence of several amines, such as aniline, benzylamine, piperidine, pyrrolidine, and morpholine. Thermolyses of the derivatives in the presence of 2,3-dimethyl-1,3-butadiene afforded 2-phosphoryl substituted 4,5-dimethyl-3,6-dihydro-2H-thiopyran S-oxide. In addition, novel phosphinecarbothioamides were obtained in the reaction of the derivatives with amines.

Molecular structures and some properties of starches from propagules of mangrove species, Rhizophora stylosa Griff. (Rs), Kandelia candel (L.) Druce (Kc), and Bruguiera gymnorrhiza (L.) Lamk. (Bg), were examined. Starch content (dry basis, %) of mature propagules was 26.8–33.9. The Rs, Kc and Bg starch showed Ca, Cb and Cc crystalline type, respectively. Pasting properties differed greatly by source especially for Kc starch having the highest peak-viscosity and ∼10 °C lower pasting temperature (68.9 °C). Actual amylose content (%) was 26.3, 24.5 and 22.3 for Rs, Kc and Bg starch. Bg amylose showed number-average degree of polymerization (DPn, determined by a fluorescent labeling method) of 840 while Rs and Kc amyloses showed larger DPn, 2620 and 2200. The mangrove amyloses contained highly branched molecules (average number of chains, 13.8–16.8) with varying proportion (14–57% by mole). DPn of Rs, Kc and Bg amylopectin was 15,700, 15,900 and 11,000, respectively. The Rs amylopectin was characteristic in that the molecular species having medium size (DPn 11,900) predominated (50% by mole). Number-average chain length (20–22) and phosphorus content (126–242 ppm) of the amylopectins were comparable to those of sweet potato amylopectins. The molar ratio of unit chains, (A+B1)/(B2+B3), was considerably different, 5.8–8.5, and the ratios indicated sparse branching of the amylopectins.

New fluoroalkyl end-capped co-oligomers containing 8-hydroxyquinolyl segments were prepared by the reactions of fluoroalkyl end-capped co-oligomers bearing isocyanato groups. The solvolysis of p -nitrophenyl propaonate (PNP) in the presence of these fluorinated co-oligomers and the corresponding  co-oligomers was investigated in 3:1 (v/v) aqueous methanol buffer solution (0.05 M phosphate, pH 9.2) at 30°C. A large rate enhancement was observed in the presence of the fluorinated co-oligomers for the solvolysis of PNP as compared with the corresponding non-fluorinated co-oligomers. Therefore, these fluoroalkyl end-capped co-oligomers are of particular interest as new fluorinated biomimetic systems for enzyme catalysts.

Three new caged nitric oxides (NOs)-BNN3, BNN5Na, and BNN5M were tested for biological use. BNNs have a strong ultraviolet (UV) absorption band (lambda(max): 300 nm, epsilon: 13.5 mM(-1) cm (-1)) extended to 420 nm and produce NO upon irradiation with 300-360 nm light in quantum yields about 2. A photoexcited BNN molecule yields two NOs with time constants of less than 10 ns for phase 1 and less than 20 micros for phase 2 at 37 degrees C, suggesting usefulness of BNNs for measuring in vivo and in vitro fast NO reactions. Upon irradiating with UV light, caged nitric oxides-loaded rat aortic strips maintained in a state of active tonic contraction effectively relaxed (3 microM BNN5M loading solution concentration). BNN3 is incorporated in the lipid membrane. BNN5Na, insoluble in organic solvents but water soluble, localizes in the water phase. BNN5M, is muscle-cell-permeable and hydrolysed to BNN5Na to remain in cytosol. BNNs were thermally stable and demonstrated no observable toxicity.

Little is known about the effectiveness of delta9-tetrahydrocannabinol (THC) and anandamide in blocking mechanical nociception. Even less is known about their antinociceptive efficacy in chronic inflammatory arthritis induced by Freund's complete adjuvant. The hypothesis was tested that THC and anandamide elicit antinociception in the paw pressure test, and that arthritic rats would exhibit a different response. In nonarthritic rats, THC- and anandamide-induced antinociception lasted 90 min and 15 min, respectively, while antinociception lasted 90 min and 30 min, respectively, in arthritic rats. Area under the curve calculations revealed no effect of arthritis on THC- and anandamide-induced antinociception. Another hypothesis was that paw pressure thresholds in arthritic rats reflect chronic cannabinoid receptor stimulation due to elevations in free anandamide levels. Yet, the CB1 receptor antagonist SR141716A failed to alter paw pressure thresholds in either nonarthritic or arthritic rats. Further investigation revealed that SR141716A significantly blocked THC antinociception, with no effect on anandamide. Thus, anandamide's effects did not result from CB1 receptor stimulation, and any potential contribution of endogenous anandamide in arthritis was not revealed. Finally, THC and anandamide appear to release an as yet unknown endogenous opioid, because naloxone significantly blocked their effects. This study indicates that anandamide and THC may act at different receptor sites to modulate endogenous opioid levels in mechanical nociception.

Rates for the reaction between L-S-nitrosocysteine and L-cysteine were found to be first order with respect to concentrations of the two reactants in the pH range of 4.85 – 9.41. The second order rate constant was determined to be 3.10 × 10−2 M−1s−1 at pH = 7.4 at 37 °C. Spontaneous decomposition of L-S-nitrosocysteine proceeded with the first order rate constant, 1.46 × 10−5 s−1 under the same conditions.

Self-assembled aggregates of fluoroalkylated end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomers selectively immobilize cytochrome c, and immobilized cytochrome c retains its catalytic activity for oxidation of guaiacol with hydrogen peroxide. In contrast, these fluorinated aggregates do not interact at all with horseradish peroxidase, bovine serum albumin, hemin, vitamin B12, or cytochrome c reductase under similar extraction conditions.

Fluoroalkylated end-capped N -(1,1-dimethyl-3-oxobutyl) acrylamide oligomer is a unique host molecule accommodating luminol and potentially enhancing light emission yield in its chemiluminescence with hydrogen peroxide-potassium ferricyanide in an aqueous solution.

An enzyme model system, consisted with TPPFe(III)Cl/imidazole has been found to catalyze hydrogen peroxide dependent S-oxygenation and oxidative S-dealkylation of organic sulfides. This biomimetic reaction has been compared with the cytochrome P-450 catalyzed H 2 O 2 dependent oxygenation.

Arenesulfonic acids, its sodium salts, and alkyl arenesulfonates were reduced readily to the corresponding arenethiols quantitatively with triphenylphosphine in the presence of iodine.

The reaction between N-tosyldiarylsulfilimines and p-toluenethiolate anion did not take place in the dark even upon heating up to 62° but proceeded smoothly upon irradiation with visible light in DMF at room temperature, affording S-N bond cleavage products.

Both the maximum velocity and the Michaelis constant of the oxygenation of N,N-dimethylaniline with the pig liver microsomal FAD-containing monooxygenase (EC 1.14.13.8) to N,N-dimethylaniline N-oxide appear 1.7 folds greater in aqueous buffer solution of pH 7.4 than those in deuterium oxide buffer solution of pD 7.4.

Reduction of Schiff bases with selenophenol proceeded at room temperature to yield the corresponding sec. amines quantitatively. The reaction of either prim. amine or sec. amine with carbonyl compound and selenophenol gave sec. or tert. amines, respectively. Different alkyl groups can be introduced successively on nitrogen of prim. amines to afford tert. amines bearing three different alkyl groups desired by one pot reaction.

Meso-tetraphenylporphinatoiron(III)/imidazole catalyses the Polonovski type reaction of substituted N,N-dimethylanilne N-oxides to give mixtures of N-demethylated and N-deoxygenated products. Effect of substituent on the turnover number and the ratio of the demethylation to the deoxygenation, and other observations suggest that the Polonovski type N-demethylation reaction takes place via the rate determining N,N-dimethylanilinium cation radical formation.

Amines, especially imidazole, were found to be essential in the meso-tetraphenylporphinatoiron (III) promoted demethylation of N, N-dimethylaniline N-oxide through the Polonovski type reaction and in the cumene hydroperoxide dependent oxidative demethylation of N, N-dimethylaniline in dichloromethane. When benzenethoil was used instead of these amines, deoxygenation of N, N-dimethylaniline N-oxide took place very readily

Mechanistic mode for the oxygenation of sulfides with the pig liver microsomal FAD-containing monooxygenase(EC 1.14.13.8) has been conveniently distinguished from that with the phenobarbital induced liver microsomal cytochrome P-450 by analyzing products of the oxygenation of phenacyl phenyl sulfide. Upon oxygenation of phenacyl phenyl sulfide, the FAD-containing monooxygenase gave solely phenacyl phenyl sulfoxide in contrast to the cytochrome P-450 promoted oxygenation which is known to give substantial amounts of C-S bond fission products. The observation suggests that the oxygenation of sulfide with FAD-containing monooxygenase involves the nucleophilic attack of the divalent sulfur on the reactive oxygen atom involved at the enzyme active site, namely electrophilic oxygenation of sulfide, though the oxygenation with the cytochrome P-450 is initiated by a single electron transfer from the sulfide to the enzyme active species.

Reduction of sulfoxides and sulfilimines to the corresponding sulfides by both BNAH and NaBH 4 have been found to proceed in the presence of a catalytic amount of metallo-mesotetraphenylporphins.

Reduction of diaryl disulfides with 1-benzyl-1,4-dihydronicotinamide (BNAH) proceeded through a radical chain reaction, while dialkyl disulfides were found to be inert to BNAH.

Relative reactivities of aromatic nitro, nitroso, hydroxylamino, azoxy, azo and hydrazo compounds in the reduction with RSe − were found to fall in the following order

Diaryl disulfides were found to be reduced smoothly to the arenethiols by BNAH in the presence of a catalytic amount of 3-methyllumiflavin under mild conditions.