• Archives of Pharmacal Research
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• v.23 no.6
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• pp.574-578
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• 2000

Protected $\alpha$-Phenyl glycine 17 and phenylalanine 18 and 19 have been synthesized through an efficient three-step sequence from the corresponding allyl ethers 5, 7, and 10. The key intermediate in this synthesis is the corresponding allylic amines prepared by reaction of allyl ethers with chlorosulfonyl isocyanate.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.239.2-240
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• 2003

We have recently described the novel synthetic method for N-protected amines from various ethers using chlorosulfonyl isocyanate(CSI) and found that the mechanism of our CSI reaction is a competitive reaction of SN1 and SNi mechanism according to the stability of carbocation intermediate. Forthermore. we developed the regioselective and diastereoselective one-pot synthetic method for 1,2-amino alcohol, through the reaction of di-and tribenzyl thers with CSI, and invetigated its mechanism. (omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.242.2-243
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• 2003

We have developed the novel one-pot synthetic method for regioselective N-protected amines, carbamates as a protective group of amines, through the reaction of various ethers with chlorosulfonyl isocyanate (CSJ). This synthetic method provides a simple and convenient alternative for the formation of carbamates, such as -NHMoc, -NHPoc. -NHCbz, -NHPnz, -NHTroc and -NHAloc, by varying the alkyl moiety of ethers. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.183.1-183.1
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• 2003

The synthesis of various cyclic carbamate compounds and amino alcohols has attracted attention in the past because of their potential as antibiotics, antitumor, analgenics, anticonvulsants. Several methods for the preparation of cyclic carbamate compounds have previously been reported including the use of heterocumulenes. We have recently described the novel synthetic method for N-protected amines from various ethers using Chlorosulfonyl isocyanate(CSI) and found that the mechanism of our CSI reaction is a competitive reaction of $S_N1$ and $S_ Ni$ mechanisms according to the stability of carbocation intermediates. (omitted)

• Archives of Pharmacal Research
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• v.28 no.4
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• pp.382-390
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• 2005

chial allylic ethers with a hydroxyl group attached to the $\pi-system$ and chlorosulfonyl isocyanate. The enantioselectivity of the CSI reaction with the chiral allylic and benzylic ethers was examined in various solvents and temperatures. Based on these results, it was proposed that the CSI reaction is a competitive reaction of a $S_{N}i$ (retention) and a $S_{N}1$ mechanism (racemization) according to the stability of the carbocation intermediate. This means that there is a greater proportion of retention with the less stable the carbocation intermediate and vise versa.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.349.2-350
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• 2002

Deprotection of the benzyl group has been widely used in multi-step organic synthesis with a variety of reaction conditions. including catalytic hydrogenolysis. Lewis acids such as FeCl$_3$ or MgBr$_2$ and lithium naphthalenide. However. these procedures sometimes can be problematic with multifunctional substrates. such as unsaturated bonds during hydrogenolysis. an acid-labile moiety in FeCl$_3$ and a easily reducible functional group in lithium naphthalenide. (omitted)

• Archives of Pharmacal Research
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• v.24 no.5
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• pp.371-376
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• 2001

The reaction of various alkyl cinnamyl ethers with CSI afforded the corresponding cinnamylamines with various protecting groups, such as -NHMoc, -NHiPoc, -NHCbz, -NHPnz, -NHTroc and -NHAloc. In the case of cinnamyl t-butyl ether and cinnamyl p-methoxybenzyl ether, the corresponding cinnamyl carbamates were formed via a different reaction pathway from the above.

• Archives of Pharmacal Research
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• v.26 no.9
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• pp.667-678
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• 2003

We examined the effect of p-substituents in p-substituted cinnamyl methyl ethers and 1-(p-substituted phenyl)allyl methyl ethers with CSI, and confirmed that the CSI reaction of allyl ethers (p-substituted ethers) is a competitive reaction of $S_Ni{\;}and{\;}S_N1$ mechanism according to the stability of the carbocation. And, the only terminal allylic amine was obtained through the migration reaction in thermodynamic reaction condition.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.179.2-179.2
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• 2003

We have developed the novel one-pot synthetic method for regioselective and stereoselective N-protected amines through the reaction of various ethers with chlorosulfonyl isocyanate (CSI). Also, we found a novel technique to compare directly the stability of carbocations in the solution phase and established the stability order of the various carbocations. And we reported the cleavage of benzyl and p-methoxybenzyl protecting groups of alcohols and phenols in the presence of other functional groups using CSI. (omitted)

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.116-116
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• 2003

In 1998, Osada and co-workers isolated 140 mg of a novel cytokine modulator from 18 L of the culture broth of Streptomyces RK95- 31 isolated from a soil sample in Hiroshima Prefecture. This new immunosuppressant was named (-)-cytoxazone and its absolute configuration was determined on the basis of its NMR, CD and X -ray analysis. It interferes with cytokine IL4, IL10 and IgG production by selective inhibition of the signaling pathway of Th2 cells, but not Thl cells. Inhibitors of Th2-dependent cytokine production have potential as potent chemotherapeutic agents in the field of immunotherapy. The (-)-cytoxazone is different from known immunomodulators such as FK 506 and rapamycin in respect of structure and biological activity. As such cytoxazone should be a useful tool for understanding signaling pathways in Th2 cells, the synthesis of (-)-cytoxazone is of interest for the development of new cytokine modulators.