• YAKHAK HOEJI
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• v.35 no.5
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• pp.368-371
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• 1991

For the development of new antiulcer agents 5, 6-dihydroimidazo[2, 1-b]- thiazoles substituted at the 3-position are sythesized. Thus, the reaction of 3-chloromethyl-5, 6-dihydroimidazo[2, 1-b]thiazole(2) with thiourea and subsequently with 3-chloro-propionitrile gives 3-[3-[5, 6-dihydroimidazo[2, 1-b]thiazolyl]methylthio]propionitrile(4), which by partial alcoholysis with methanol is converted into methyl-3-[3-[5, 6-dihydro-imidazo[2, 1-b]thiazoyl]methylthio]propionimidate(5) . This compound(5) is treated finally with sulfamide or sulfonamides. 3-[3-[5, 6-dihydroimidazo[2, 1-b]thiazoyl]methylthiol-N$^{2}$-sulfamoyl-propionamidine(6) inhibited gastric acid secretion (45%) when administered intraduodenally (100 mg/kg) to pylorus-ligated rats.

• Journal of the Korean Chemical Society
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• v.47 no.1
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• pp.38-42
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• 2003

For the purpose of developing new agrochemical fungicides, compound 2 possessing 1,3-thiazole scaffold as well as urea moiety in the structure was designed through molecular modification of lead compound, 2-imino-1,3-thiazoline based on isosterism. The reaction of N-methylthiouea 5 and bromoacetonitrile in ethanol gave 2,4-diimino-1,3-thiazole 4 regioselectively, which was treated with phenyl isocyanates to give the corresponding 7 which is tautomer of 2. The structural assignment of 7 was confirmed by various spectra($^1H$ NMR, $^{13}C$ NMR, FT-IR, HRMS), and X-ray crystallographic data. Compound 8 which is a structural isomer of 7 was formed through thermodynamically unstable intermediate 2,4-diimino-1,3-thiazole 6.

• YAKHAK HOEJI
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• v.29 no.1
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• pp.39-42
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• 1985

Betaines of bicyclic imidazo-thiazoles were synthesized by the reaction of clectrophiles such as methyl isocyanate, methyl isothiocyanate, allyl isothiocyanate and ketene with 3-methyl and 3-phenyl-5, 6-dihydroimidazo [2,1-b] thiazole. In this reaction, the methyl group which was substituted at 3-position increased the yields of the products in comparison with those from phenyl group substituted substrates. Also, the betaines reacted with methyl iodide to give imidazo-thiazolium salts which were unstable at high temperature and converted the quaternary ammonium salts of original biheterocycles.

• Archives of Pharmacal Research
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• v.23 no.5
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• pp.446-449
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• 2000

Imidazonaphthothiazole derivatives 3∼6 were prepared by treatment of 2-aminonaphtho[2,3-d]-thiazole-4,9-dione(1) with phenacyl bromide, chloroacetic acid, diethyl oxalate and 2,3-dichloroquinoxaline respectively. The reaction of 1 with ethyl acrylate, ethyl acetoacetate and diethyl malonate gave the corresponding naphthothiazolopyrimidine derivatives 8∼11.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2337-2340
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• 2010

A series of new 6-aryl-3-(3,4-dimethoxy-phenyl)-2-phenylsulfanyl-imidazo[2,1-b]-thiazole (5a-c) and 6-aryl-2-benzenesulfonyl-3-(3,4-dimethoxy-phenyl)imidazo[2,1-b]- thiazole (6a-c) have been prepared and characterized by analytical and spectral methods. The title compounds 5a-c and 6a-c were obtained by the reaction of 4-(3,4-dimethoxy-phenyl)-5-phenylsulfanyl-thiazol-2-ylamine (3) and 5-benzenesulfonyl-4-(3,4-dimethoxy -phenyl)thiazol-2-ylamine (4) with various phenacyl bromides in anhydrous ethanol. These newly synthesized compounds (5a-c and 6a-c) were screened for their anthelmintic and anti-inflammatory activities, where they have displayed better activities.

• The Korean Journal of Pharmacology
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• v.29 no.2
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• pp.275-282
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• 1993

Liver microsomal epoxide hydrolase (mEH) is active in the detoxification of epoxide-containing reactive intermediate. Previous studies in this laboratory have shown that thiazole and pyrazine are efficacious inducers of mEH in rats with large increases in mEH mRNA levels (Carcinogensis, Kim et al, 1993). mEH was purified to electrophoretic homogeneity from thiazole-induced rat hepatic microsomes using DEAE-cellulose column chromatography whereas another protein $({\sim}43\;kDa)$ was co-purified with mEH from pyrazine-induced rat hepatic micrsomes (200 mg/kg body weight/day, ip, 3d). The antibody raised from a rabbit against mEH protein purified from thiazole-induced rat hepatic microsomes appeared to specifically recognize mEH protein in rat hepatic microsomes, as assessed by immunoblotting analysis. Immunoblotting analyses revealed a 10- and 7-fold increase in mEH levels in the hepatic microsomes isolated from thiazole- and pyrazine-treated rats, respectively. Moreover, immunoblotting analysis showed cross-reactivity of the mEH antibody with a 43 kDa protein in pyrazine-induced rat hepatic microsomes and with co-purified 43 kDa protein in purified fractions. The ratio between the 43 kDa protein and mEH in pyrazine-induced rat microsomes or in purified fractions was ${\sim}1$ to 15. N-terminal amino acid sequence analysis of both purified rat mEH and 43 kDa protein revealed that 10 out of 12 amino acids in N-terminus of the 43 kDa protein were identical with the mEH sequence with two amino acid residues of the 43 kDa protein undetermined. Either thiazole or pyrazine treatment, however, failed to increase the levels of mEH protein in rabbits while pyrazine caused elevation of the 43 kDa protein in this species, as determined by irnrnunoblotting analysis. These results demonstrated that treatment of rats with either thiazole or pyrazine causes elevation in hepatic mEH expiession whereas pyrazine treatment results in induction of another mEH-related 43 kDa protein and that a distinct species difference exists between rats and rabbits in the induction of mEH by these xenobiotics.

• Applied Chemistry for Engineering
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• v.18 no.4
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• pp.326-329
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• 2007

2-Arylidenehydrazinyl-4-arylthiazole derivatives (9a-f) were prepared by the in situ formation of ${\beta}$-cyclodextrin complex of 2,4'-dibromoacetophenone (8) in water followed by the addition of arylidenethiosemicarbazones (7a-f) in 70~88% yield. The structures of the compounds 9a-f were elucidated by IR and $^1H-NMR$ spectral data. The role of ${\beta}$-cyclodextrin appears to activate the compound 7 and 8 and promote the reaction to complete in reduced reaction time.

• Bulletin of the Korean Chemical Society
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• v.25 no.10
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• pp.1465-1470
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• 2004

A short and efficient synthesis, solvent extraction and potentiometric measurements of new thiazole-containing naphtho-crown ethers are reported. The naphthalene moiety enhances the ammonium ion selectivity over potassium ion. The selectivity of ${NH_4}^+/K^+$ follows the trend $3\;{\approx}\;2\;>\;1$, indicating that the differences in conformational changes of 2 and 3 in forming ammonium complexes affect little on the resulting ammonium/potassium extraction selectivity ratio. The ammonium ion-selective electrodes were prepared with noctylphenyl ether plasticized poly(vinyl chloride) membranes containing 1-4 the effect of one naphthalene unit introduced on either right (2) or left (3) side of thiazolo-crown ether on their potentiometric properties (e.g., ammonium ion selectivity over other cations, response slopes, and detection limits) were not apparent. However, the ammonium ion selectivity of 1, 2 and 3 over other alkali metal and alkaline earth metal cations is 10-100 times higher than that of nonactin.

• Journal of the Korean Chemical Society
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• v.34 no.1
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• pp.102-107
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• 1990

The reaction of thiazoline-azetidinone (7) with $I_2$ in $CH_2Cl_2-H_2O$ gave directly 3-iodo-3-methylcepham (4). A phase transfer catalyst considerably increased the reaction rate. Similar to the hydrolysis of thiazoline-azetidinone (7) under a weak acidic condition, thiazole (10) was given as major product in the treatment with 0.1 eq. of iodine. The difference between cyclization reaction and hydrolysis could be explained in terms of solvents, the amount of iodine and the nature of thiazoline-azetidinones (7).

• Archives of Pharmacal Research
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• v.13 no.3
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• pp.261-264
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• 1990

4-Arylazo-3-phenyl-5-aminopyrazoles (5a, b) and substituted hydroxythiazoles 8a, b were synthesized from the reaction of 4a, b with hydrazine hydrate and mercaptoacetic acid respectively. Compounds 5a, b and 8a, b were also obtained from coupling of 2a, b with 6 and 7, respectively. 4H-1, 4-Benzothiazine 11 was prepared from 1 and 10. The resaction of the diazonium salts 2a-c with diethyl 3-amino-2-cyanopenet-2-en-1, 5-dicarboxylate 12 was also reported.