- Structure and synthesis of 3,5-dimethyl-N-nitro-1H-pyrazole-1-carboxamidine
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A new approach to the synthesis of 3,5-dimethyl-N-nitro-1H-pyrazole-1-carboxamidine was developed based on condensing 1-amino-2-nitroguanidine with pentane-2,4-dione under alkaline catalysis. The known method of its preparation in the presence of acetic acid was improved. The structure of 3,5-dimethyl-N-nitro-1H-pyrazole-1-carboxamidine was characterized by NMR, IR spectroscopy and X-ray diffraction analysis.
- Ozerova,Efimova,Novikova,Gurzhii,Berestovitskaya
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- NOVEL IMIDAZOLE DERIVATIVES, PREPARATION AND USER THEREOF AS MEDICINE
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The invention concerns novel imidazole derivatives of general formula (I), wherein Z′ and Z represent different variable groups. Said products have an antitumoral activity. The invention also concerns pharmaceutical compositions containing said products and their use for preparing antitumoral medicine.
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Page/Page column 8
(2009/07/25)
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- Optimisation of the synthesis of guanidines from amines via nitroguanidines using 3,5-dimethyl-N-nitro-1H-pyrazole-1-carboxamidine
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The synthesis of the useful reagent for the preparation of guanidines, 3,5-dimethyl-N-nitro-1-pyrazole-1-carboxamidine (DMNPC), has been optimised. A detailed protocol for using this reagent for the preparation in pure form of a range of guanidines via nitroguanidines is described. A comparison has been made regarding efficiency between DMNPC and the guanidinylating reagents N,N′-bis-Boc-1-pyrazole-1-carboxamidine (2) and N,N′-bis-Boc- N′-triflylguanidine (3).
- Castillo-Melendez, Joel A.,Golding, Bernard T.
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p. 1655 - 1663
(2007/10/03)
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- Protecting-group strategies for the synthesis of N4-substituted, and N1,N8-disubstituted spermidines, exemplified by hirudonine
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Methods are described for the preparation of derivatives of the polyamines 1,4-diaminobutane (putrescine), and N′-(3-amihopropyl)-l,4-diaminobutane (spermidine) in which a particular amino group is modified with, e.g., a guanidino function. Specific amino groups in these polyamines were protected as ;V-trifluoroacetyl, and yV-4-azidobenzyloxycarbonyl derivatives, which were unmasked chemoselectively using methanolic ammonia, and dithiothreitol-triethylamine, respectively. Guanidino functions were introduced by an improved procedure in which an amino group was treated with 3,5-dimethyl-Ar-nitro-!//-pyrazole-l-carboximidamide in methanol to give a nitroguanidine derivative, from which the nitro group was removed by catalytic transfer hydrogenation. The methodology is exemplified by the development of efficient preparative routes to agmatine, and hirudonine. The integrity of the sequence of protection/deprotection leading to hirudonine was confirmed by a crystal-structure analysis of its sulfate. The effect of selected compounds on the uptake of putrescine into rat lung cells was determined, and showed that N4-(4-azidobenzyloxycarbonyl)spermidine was the best inhibitor (Ki = 3.4 μM).
- Golding, Bernard T.,Mitchinson, Andrew,Clegg, William,Eisegood, Mark R. J.,Griffin, Roger J.
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p. 349 - 356
(2007/10/03)
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