• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1539-1542
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• 2011

The aminolysis of O-methyl S-aryl thiocarbonates with benzylamines are studied in acetonitrile at -45.0$^{\circ}C$. The ${\beta}_X$(${\beta}_{nuc}$) values are in the range 0.62-0.80 with a negative cross-interaction constant, ${\rho}_{XZ}$ = -0.42, which are interpreted to indicate a concerted mechanism. The kinetic isotope effects involving deuterated benzylamine nucleophiles ($XC_6H_4CH_2ND_2$) are large, $k_H/k_D$ = 1.29-1.75, suggesting that the N-H(D) bond is partially broken in the transition state by forming a hydrogen-bonded four-center cyclic structure. The concerted mechanism is enforced by the strong push provided by the MeO group which enhances the nucleofugalities of both benzylamine and arenethiolate from the putative zwitterionic tetrahedral intermediate.

• Bulletin of the Korean Chemical Society
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• 제12권1호
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• pp.101-103
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• 1991

The kinetic isotope effects (KIE) are determined for the reactions of benzyl benzenesulfonates (BBS), ethyl benzenesulfonates (EBS) and phenacyl benzensulfonates (PAB) with deuterated benzylamine nucleophiles. The inverse secondary ${\alpha}$-deuterium KIE observed were somewhat smaller than those for the corresponding reactions with aniline nucleophiles. The primary $KIE_s$ obtained with PAB were slightly greater than those for the corresponding reactions with anilines, which suggested that the inverse secondary KIE is decreased due to a relatively earlier transition state for bond-making with little change in the hydrogen bonding strength to the carbonyl oxygen.

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of International Convention of the Pharmaceutical Society of Korea
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• pp.283.2-283.2
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• 2001

• 농약과학회지
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• 제5권2호
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• pp.13-17
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• 2001

새로운 살균제를 개발할 목적으로 새로운 2-phenylimino-1,3-thiazoline 유도체를 합성하였다. Ketone dimer를 염소와 반응시킨 다음 중간체 8a의 분리없이 benzylamine으로 처리하여 ${\gamma}-Chloro-{\beta}-keto$ benzylamide 10a를 얻었다. Methyl isothiocyanate와 aniline 유도체의 반응에서 얻은 thiourea 4를 10a와 acetone 용액 중에서 반응시켜 분리 불가능한 중간체 11 및 12를 거쳐 각각에 상응하는 2-phenylimino-1,3-thiazoline 유도체의 염산염 2를 얻었다. Thiourea 4의 phenyl기에 인접한 질소원자의 비공유 전자쌍의 도움으로 황원자의 친핵적 공격을 포함한 가능한 반응 mechanism을 논의하였다.

• 한국식품위생안전성학회지
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• 제10권4호
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• pp.279-282
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• 1995

Eight natural or semistynthesized monoterpenes were examined for their effects in rat brain monoamine oxidase(MAO) using benzylamine as substrate. Thujone and 3-carene were found to have the inhibition effects on rat brain MAQ activity, 38% and 95% inhibition at 103M respectively. The kinetic study on 3-carene, the most potent inhibitive type. But (+) pulegon and (-) isopulegon was found to activate MAO slightly.

• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.657-661
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• 1995

Kinetic studies are carried out on the reaction of S-phenyl dithiobenzoates with benzylamines in acetonitrile at 30.0 ℃. Small magnitude of ρX (βX) as well as ρZ (βZ) obtained suggests rate-limiting nucleophilic attack of the thiocarbonyl carbon. This is supported by the unusually small magnitude of ρXY and ρYZ, albeit their signs do not agree with those expected. Moreover, the inverse secondary kinetic isotope effects (kH/kD<1.0) involving deuterated benzylamine nucleophiles are also in line with the proposed mechanism.

• 한국식품과학회지
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• 제37권1호
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• pp.95-102
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• 2005

상심자 추출물이 운동에 의한 체내 monoamine oxidase (MAO) 활성 변화에 미치는 영향을 연구하여. 상심자 추출물을 경구투여(0.3g/kg body weight) 한 흰쥐의 뇌와 간에서 MAO-A와 MAO-B의 활성에 중요한 영향을 미치는 사실을 확인하였다. 각 효소활성은 serotonin과 benzylamine을 기질로 이용하여 측정하였다. 운동 전 후 운동의 유형에 따라 효소활성의 변화경향이 서로 다른 경향을 나타내었다. 뇌에서 측정한 MAO-A 활성은 운동에 의해 효소활성이 현저히 감소하였으며 반면, 간에서 측정한 MAO-B의 활성은 운동이 끝나고 60분이 경과할 때까지 증가된 상태를 유지하고 있었다. 운동 시 체내 변화의 지표효소인 혈중 LDH의 활성 변화와 혈중 lactate의 농도변화를 함께 관찰함으로서 MAO 활성과의 상관관계를 비교하였다. 상심자 추출물을 경구투여 하고 운동을 한 동물의 MAO-A 활성은 증가하였고 MAO-B, LDH 활성과 lactate level은 감소하는 것을 확인하였다. 결과적으로 모은 지표들이 운동 전의 정상상태로 회복되는 것으로 확인되었다. 이 연구의 결과들로부터 상심자 추출물이 운동 전후의 MAO 활성을 조절함으로써 운동능력을 향상시키고 피로를 회복하는 효능을 갖는 것으로 추정되며 이러한 기능성을 갖는 건강기능식품의 소재로 활용이 가능할 것으로 생각한다.

• 생약학회지
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• 제34권2호통권133호
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• pp.185-189
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• 2003

We examined the inhibitory activities against monoamine oxidase (MAO) of Morus alba in vitro and in vivo methods. Methanolic extract of M. alba showed significantly inhibitory activities on MAO-A and MAO-B that were prepared from rat brain and liver in vitro. The inhibitory activities were measured by serotonin and benzylamine as substrates, respectively. MAO-A and MAO-B activities were potently inhibited by ethylacetate extracts of M. alba in vitro tests. Those activities in vivo tests have different tendency each other. MAO-A activity was increased by the oral administration of methanolic extract of M. Alba, while, MAO-B activity was decreased. Consequently, we can suggest that M. alba may have the effects on the inhibitory activities against MAO both in vitro and in vivo.

• 대한약리학회지
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• 제8권2호
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• pp.41-47
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• 1972

Fluorides were supposed to exert a stimulatory action on the catecholamine release. In this study, the authors attempted to investigate the action of sodium fluoride on the catecholamine release from the isolated perfused cow adrenal gland and rat heart. And also the inhibitory effect of sodium fluoride on the monoamine oxidase activity in rat heart and liver mitochondria was investigated. The monoamine oxidase activity was measured by the conversion of benzylamine to benzaldehyde. The results obtained were follows; 1. Sodium fluoride stimulated the release of catecholamine from the isolated perfused cow adrenal gland and rat heart. 2. Sodium fluoride inhibited the rat heart and liver mitochondrial monoamine oxidase activity.

• 생약학회지
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• 제37권3호
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• pp.157-161
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• 2006

We examined the inhibitory activities against monoamine oxidase (MAO) of Prunella vulgaris in vitro and in vivo methods. Methanolic extract of P. vulgaris showed significantly Inhibitorγ activities on MAO-A and MAO-B that were prepared from rat brain and liver in vitro. The inhibitory activities were measured by serotonin and benzylamine as substrates, respectively. MAO-A and MAO-B activities were potently inhibited by ethylacetate extracts of P. vulgaris in vitro tests. It was observed that those activities in vivo tests have different tendency each other. MAO-A activity was increased by the oral administration of methanolic extract of P. vulgaris while MAO-B activity was decreased. Consequently, we suggest that P. vulgaris may have the effects on the inhibitory activities against MAO both in vitro and in vivo.