• Archives of Pharmacal Research
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• v.23 no.2
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• pp.99-103
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• 2000

Acid and base catalyzed intramolecular cyclizations of N-benzoylthioureidoacetal, contain-ing four functional groups adjacent to thiourea such as benzocarbamoyl, acetal, thioure and amide, were investigated. The condensation reaction of N-benzoyl thiocarbamoylgly-cine amide in the presence of 10% aqueous NaOH provided 1-(2,2-dimethoxy)ethyl-imi- dazolidine-2-thione exclusively. In the presence of pyridine, it was transformed to 2- thiohydantoin. N-Benzoyl thiocarbamoyl glycine amide was completely transformed to an iminothiazolidine exclusively in the presence of Lewis acid such as borontrifluoride ether-ate or trimethylsilyl iodide. 1-(2,2-Dimethoxy)ethyl-imidazolidine-2-thione was transformed to imidazole[2,1-b]thiazole and pyrazino[5,1-a]imidazole in the presence of $BF_3$.$ET_2$O and formic acid, respectively.

• Archives of Pharmacal Research
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• v.29 no.1
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• pp.40-45
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• 2006

Several diacetoxy acetal analogues have been synthesized from santonin and assessed for their ability of inducing or enhancing the differentiation of human HL-60 leukemia cells. The compounds themselves had little effect on HL-60 cell differentiation. However, three analogues, 2a, 3a, and 5b, synergistically enhanced 1,25-dihydroxyvitamin $D_3[1,25-(OH)_2D_3]-induced$ HL-60 cell differentiation when combined with 5 nM of dihydroxyvitamin $D_3[1,25(OH)_2O_3]$, a well-known differentiation inducer. Especially, the compound 5b profoundly enhanced the $1,25-(OH)2O_3]-induced$ HL-60 cell differentiation.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.175-178
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• 2011

A facile, convenient, efficient and high yielding synthesis of a combinatorial library of coumarins has been developed by the condensation of readily available $\beta$-oxodithioesters and S,S-acetal with 2-hydroxy-1-naphthaldehyde in the presence of catalytic amount of $CuCl_2$ under solvent free conditions.

• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.779-782
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• 2002

• Bulletin of the Korean Chemical Society
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• v.21 no.5
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• pp.457-458
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• 2000

• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.392-397
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• 2007

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2776-2778
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• 2011

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1465-1466
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• 2010

• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.551-553
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• 1992

An efficient and very short synthesis of epoxy alcohol 5, a key intermediate for leukotriene synthesis, was described. The key reaction involves the regioselective benzylidene acetal formation from methyl 5,6,7-trihydroxyheptanoate 1.

• Bulletin of the Korean Chemical Society
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• v.19 no.2
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• pp.226-230
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• 1998

1-Alkoxymethylphosphonates 4 and 1-alkylthiomethylphosphonates 5 can be prepared by the reaction of actal derivatives and diethyl trimethylsilyl phosphite in the presence of Lewis acid under mild conditions. The dependency of the chemoselectivities with Lewis acid on the reaction of O,S-acetals with phosphites is described.