• Journal of the Korean Chemical Society
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• v.54 no.4
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• pp.437-442
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• 2010

Sodium hydrogen sulphate ($NaHSO_4$), n-tetra butyl ammonium bromide (TBAB) as a phase transfer catalyst (PTC) in water, and 1-butyl-3-methyl imidazolium hydrogen sulphate [bmim]$HSO_4$ as ionic liquid (IL) has been used as a mild reaction promoter for the cyclocondensation of formalin, ${\beta}$-naphthol and aromatic amines to afford respective 2,3-dihydro-2-phenyl-1H-naphtho-[1,2-e] [1,3] oxazine derivatives. The present protocols are greener, high yielding and involved the nonchromatographic isolation procedure.

• YAKHAK HOEJI
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• v.52 no.6
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• pp.488-493
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• 2008

2-Aminothiazole ring as a bioisoster of catechol in dopamine has provided with good oral availability and lipophilic property. 2-Aminoindan, is a rigid form of dopamine, was evaluated as a dopamine D3 agonist with low neurotoxicity. Dopamine D3 agonist was evaluated as selective for the treatment of Parkinson's disease. In order to develop a novel dopamine D3 agonist, we tried to synthesize the aminothiazoloindenoxazine derivative that is a hybrid structure of aminoindenoxazine and thiazole ring. cis-2-Amino-1-indanol (2) was synthesized from 1,2-indandione-2-oxime by catalytic hydrogenation and it was treated with chloroacetyl chloride and NaH in benzene solution to give (${\pm}$)-cis-4,4a,5,9b-tetrahydroindeno[1,2-b][1,4]oxazin-3(2H)-one (6). Nitration of 6 by the mixed acid gave 8-nitro compound (7) and the carbonyl group of 7 was reduced with $LiAlH_4$ to afford compound (8). 8 was reduced to form (${\pm}$)-cis-8-amino-2,3,4,4a,5,9b-hexahydroindeno[1,2-b][1,4]oxazine (9) and finally it was cyclized with KSCN in glacial acetic acid to yield (${\pm}$)-cis-8-amino-2,3,4,4a,5,10b-hexahydrothiazolo[4,5-f]indeno[1,2-b][1,4]oxazine (10).

• Archives of Pharmacal Research
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• v.16 no.2
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• pp.158-160
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• 1993

2-Oxazolidinones and 1,3-oxazine-2-ones, key moieties of new antiulcer agents, were prepared successfully by treating corresponding hydroxyamide with N-bromosuccinimide (NBS) and silveracetate in acetonitrile. From the fact that the methods for the preparation of hydoxy amides are versatile and such amides could be converted to the corresponding 2-oxazolid-iones and 1,3-oxazine-2-one under our reaction condition, we think that our method is very practical one for the preparation of such compounds. In addition, the above synthetic example affords a good evidence of the synthetic applicability of our improved Hofmann rearrangement.

• Archives of Pharmacal Research
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• v.13 no.1
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• pp.97-100
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• 1990

A convenient route is reported for the synthesis of fused pyrrolo [2, 3-d][1, 3]-oxazine and pyrrolo [2, 3-d]-pyrimidine derivatives from 2-amino-1-benzyl-3-t-butoxy-carbonyl-4, 5-dimethylpyrrole.

• YAKHAK HOEJI
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• v.31 no.4
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• pp.219-223
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• 1987

2-Cyclohexylimino-3-cyclohexyl-5-methyl-4-oxo-2H, 5H-1, 3-oxazino [5,6-C]-1, 2-benzothiazine-6,6-dioxide 2 was hydrolized in d-HCl/$CH_3$CN to give 5-methyl-3-cyclohexyl-2H, 5H-1, 3-oxazino [5, 6-C]-1, 2-benzothiazine-2, 4(3H)-dione 6, 6-dioxide 3 in 82% yield. The alkaline hydrolysis of 3 afforded to 4-hydroxy-2-methyl-N-(cyclohexyl)-2H-1, 2-benzothiazine-3-carboxamide-1, 1-dioxide 4 in 88% yield. On the other hand 3 was synthesized from 4 and ethylchloroformate on the reversed procedure.

• Bulletin of the Korean Chemical Society
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• v.17 no.2
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• pp.115-116
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• 1996

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1657-1660
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• 2010

An efficient and novel one-pot synthesis of new 3,4-dihydro-3-substituted-2H-naphtho[2,1-e][1,3]oxazine derivatives from 1-naphthol, various anilines and formalin at room temperature grinding is presented. The six-membered N,O-heterocyclic skeleton was constructed via zirconyl(IV) chloride promoted Mannich type reaction. In vitro antimicrobial activities of synthesized compounds have been investigated against Gram-positive Bacillus subtilis, Gram negative Escherichia coli and two fungi Candida albicans and Aspergillus niger in comparison with standard drugs. The results of preliminary bioassay indicate that some of title compounds possess significant antibacterial and antifungal activity.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2486-2488
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• 2007

• Polymer(Korea)
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• v.35 no.4
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• pp.308-313
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• 2011

The ring-opening isomerization polymerization behavior of 2,5,6,7-tetrahydro-3H-imidazo[2,1-b] [1,3] oxazine(TII) has been studied under various conditions. The present study aimed at improving the low polymerizability of the above monomer (six-membered ring) up to a level comparable to that of 2,5,6-tetrahydroimidazo[2,1-b] [l,3] oxazole(TIO) (five-membered ring). The optimum result could be observed when methyl trifluoromethanesulfonate(MeOTf) and nitrobenzene were used as an initiator and a solvent in the polymerization at $60^{\circ}C$ for 24 h. Polymers were confirmed by$^1H$ NMR과$^{13}C$ NMR, and m measurements. The molecular weight obtained by gel permeation chromatography (GPC) corresponded to the molecular weight theoretically calculated from the feed ratio. The melting temperature ($T_m$) of TII was conspicuously different from that of TIO, because of the difference in the alkyl group.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1481-1484
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• 2006