- Design, synthesis and anti-tumoractivity of novel amidine derivatives of doxifluridine
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A series of novel amidine derivatives of doxifluridine were synthesized using acid amide as the starting material, and their anti-tumor activity was evaluated in A549 cells. Compounds 10 and 11 demonstrated were more potent than 5-Fu, which was used as a positive control. Compound 10, which were found to be the most potent one with IC50 of 3.2 μmol/L, was 16 times more potent than 5-Fu with IC50 of 52 μM to the A549 cells. A new route was designed to synthesize 5′-deoxy-5-fluorocytidine. All compounds were characterized by 1H NMR, MS and X-ray spectras in detail.
- Feng, Ji Lu,Sun, Hai Ling,Geng, Dong Ping,Li, Ke
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- Degradation of cellulosic materials by heating in DMAc/LiCl
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N,N-Dimethylacetamide (DMAc, 1)/lithium chloride is a frequently used solvent system for cellulosic materials. Heating or refluxing insoluble samples in DMAc/LiCl represents a common protocol for facilitating the subsequent dissolution. It is shown by kinetics using gel permeation chromatography (GPC) that the improved solubility is not caused by an alleged 'activation' of the pulp, but by progressing degradation of the cellulosic material. Ketene aminal 2 and N,N-dimethylketeniminium ions (3), the latter being known as reagent for cleavage of ethers and acetals, have been demonstrated to be present in DMAc and DMAc/LiCl at elevated temperatures by specific trapping of these intermediates in a Claisen rearrangement and in a thermal [2+2]-cycloaddition, respectively.
- Potthast, Antje,Rosenau, Thomas,Sixta, Herbert,Kosma, Paul
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- Novel and efficient one-pot synthesis of N'-alkyl-N,N-dimethylacetamidines
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An efficient method for the synthesis of N'-alkyl-N,N-dimethylacetamidine derivatives under mild conditions and in excellent yields involved reacting primary alkylamines with N,N-dimethylacetamide in the presence of LiCl as a catalyst and methanol as the acetalising reagent.
- Li, Zhe-Qi,Wang, Hui-Long
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- HETEROCYCLIC INDOLE DERIVATIVES AND MONO- OR DIAZAINDOLE DERIVATIVES
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Indole derivatives and mono- or diazaindole derivatives represented by general formula (1), pharmaceutically acceptable acid-addition salts or base-addition salts thereof or hydrates of the same which have a COX-2 inhibitory activity and are useful as drugs such as anti-inflammatory agents, wherein Het represents an optionally substituted heterocycle; A1 and A2 independently represent each -CH=, etc.; A3 represents -CH2-, etc.; R1 represents 4-fluorophenyl, etc.; R2 represents alkyl; and n is 0, 1 or 2, provided that when A1 and A2 are both -CH=, then A3 is -CH2- or -SO2-.
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- Pyrazolo[1,5-a]pyrimidines
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This disclosure describes certain pyrazolo[1,5-a]pyrimidines useful as hypotensive and/or anxiolytic agents, or as agents for the treatment of cognitive and related neural behavioral problems in mammals.
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- KONETICS OF THE REACTION OF GUANYL-O-METHYLISOUREA HYDROCHLORIDE WITH DIMETHYLFORMAMIDE DIMETHYLACETAL
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The reaction of guanyl-O-methylisourea hydrochloride (IV) with dimethylformamide dimethylacetal (V) proceeds in two steps.The first step consists in the reaction of the imidoester with the imidatonium ion formed in a fast pre-equilibrium to give a conjugated system with the absorption maximum at 278 nm.The subsequent slower step consists in the cyclization to 2-amino-4-methoxy-1,3,5-triazine (VI).The rate of the first step is directly proportional to the concentrations of both hydrochloride IV and acetal V.Both the steps involve base catalysis.Mechanism of the whole reaction is suggested on the basis of the kinetic results.
- Kavalek, Jaromir,Panchartek, Josef,Potesil, Tomas,Sterba, Vojeslav
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p. 1964 - 1971
(2007/10/02)
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- Bis-amidines
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Symmetrical bis-amidine derivatives of mitomycin C may be converted to unsymmetrical bis-amidine analogs by reaction with secondary amines. The compounds are active anti-tumor agents in experimental animal tumors.
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- PHOTOCHEMICAL REACTIONS OF PHOSPHAALKENES
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Photolysis of phosphaalkenes leads to an inversion of polarity of the phosphorus carbon double bond and to a cleavage into transient phosphinidene and carbene; unexpected alcoholysis of a PIII-C bond and the cycloaddition of a linear phosphaalkene on a diene are also reported.
- Meriem, Abdelkader,Majoral, Jean-Pierre,Revel, Monique,Navech, Jacques
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p. 1975 - 1978
(2007/10/02)
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- Process for preparation of adjacently disubstituted ketones
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A novel 7-hydroxyprostaglandin E1, or a stereoisomer thereof, or a protected derivative thereof, having the following formula: STR1 wherein R8 represents H, CH3 or C2 H5, R9 represents H or CH3, R10 and R11 are identical or different, and each represents H, tetrahydropyranyl or t-butyldimethylsilyl. Also provided is a process for producing an adjacently disubstituted ketone including the above compounds, i.e. 7-oxoprostaglandin, etc. which comprises reacting an α,β-unsaturated carbonyl compound with a cuprous salt and an organolithium compound in an aprotic inert organic medium in the presence of trialkylphosphine, the amounts of said cuprous salt and said organolithium compound being substantially equimolar, and reacting the product with a protected acetal derivative of an organic carbonyl compound or an aldehyde in the presence of a Lewis acid, if necessary, followed by reacting the product with a proton donor.
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