Pyrimidines 4-hydroxy

Einige Pyrimidine und 2-Hydroxy-pyrimidine liefem in schwach saurem Medium neben den Tetrahydro-pyrimidinen Dihydro-Dimere. Amino-Substituenten werden als Ammoniak abgespalten (geteilte Zelle, Quecksilber-Kathode)3. 

In this paper, we briefly review the results of our work on the iodine interaction with the thioamides benzothiazole-2-thione (BZT) (1), 6-n-propyl-2-thiouracil (PTU) (2), 5-chloro-2-mercaptobenzothiazole (CMBZT) (3), N-methyl-benzothia-zole-2-thione (NMBZT) (4), benzimidazole-2-thione (BZIM) (5), thiazolidine-2-thione (TZD) (6), 2-mercapto-pyridine (PYSH) (7), 2-mercapto-nicotinic acid (MNA) (8), 2-mercapto-benzoic acid (MBA) (9) and 2-mercapto-pyrimidine (PMT) (10), selenoamides, derived from 6-n-propyl-2-thiouracil (RSeU) (R= Me- (11), Et- (12), n-Pr- (13) and i-Pr- (14)) and amides 2-hydro -pyridine (PYOH) (15) and 2-hydroxy-pyrimidine (PMOH,+ Cl ) (16)... 

Fig. 15.1. The four bases found in the nucleic acids. Uracil occurs in RNA and is substituted by the analogous thymine (5-methyluracil) in DNA. Uracil is the keto tautomer of 2,4-dihydroxy pyrimidine with two donors N(1)H, N(3)H and two acceptors 0(2), 0(4). Cytosine is the keto tautomer of 4-amino, 2-hydroxy pyrimidine with three donors N(4)H2, N(1)H and two acceptors 0(2), N(3). Adenine is 6-aminopurine with three donors N(6)H2, N(9)H and three acceptors N(l), N(3), N(7). Guanine is the keto tautomer of 2-amino, 6-hydroxy purine with three donors N(2)H2, N(9)H and three acceptors, N(3), N(7), 0(6). In the nucleosides, pyrimidine N(l) and purine N(9) are substituted by ribose or deoxyribose (see Fig. 17.1)...

The preparation of 9-niethyl and 9-butyl-2-hydroxy-8,9-dihydro-7H-purine-8-thione (XXVa Table 7) is somewhat unusual. Brown [45) has obtained these compounds from carbon disulfide and respectively f-methyl and 1 -butyl-5,6-diamino-1,2-dihydropyrimidin-2-one (XXIVa.). Evidently a shift of the alkyl group from the 3-N to the 9 N atom must occur during the ring closure. The structure of these two purines has been confirmed by their independent synthesis from 4-methylamino and 4-butylamino-5-amino-2-hydroxy pyrimidine. 

Eine Photoaddition findet zwischen Benzo- [a]-pyren und z. B. 4-Aniino-2-hydroxy-pyrimidin (Cytosin) statt, wenn man in 4%iger, waBriger Natrium-dodecyl-sulfat-Losung belichtet. Bessere Ausbeute erhalt man mit 0,2m Xatronlauge 4-Amino-6-... 

Finally the amides pyridone-2-one (PYOH) (15) and 2-hydroxy-pyrimidine (PMOHj Cl ) (16) react with and produce the complexes [(PYOH)j[(PYOH)], (PYOH) [(PYOH) F- ((1/2)T) ((3/2)I ) (I ) and [PMOHJ+CTIj. The structures of all these compounds are discussed. 

Fluorocytosine 4-Amino-5-fluoro-2-hydroxy- pyrimidine C4H4FN3O 2022-85-7 129.092 wh cry 296 dec ... 

Partly saturated pyrazino[l,2-r-]pyrimidines were prepared by formation of the pyrazine ring. 2-Substituted-8-hydroxy-3,4-dihydro-177,277-pyrazino[l,2-r-]pyrimidin-l-ones were prepared by a [6+0] synthesis involving cyclization of 6-hydroxy-pyrimidine-4-(fV-hydroxyethyl)carboxamides <2005W02005/087766>. The 2/7-pyra-zino[l,2-c]pyrimidine-3-carboxamide 164 (Y = NH) was formed from [5+1] atom fragments via the uracil derivative 163 (Y = NH) and DMF-dimethyl acetal. Compounds 163 were prepared from 6-chloromethyluracil and glycine methyl ester 162 (Y = NH) (Scheme 20) <2004W02004/014354>. 

The deoxyuracil derivatives-2-hydroxypyrimidine (69) (2-pymoH), 4-hydroxy-pyrimidine (70) (4-pymoH), 4,6-dimethyl-2-hydroxypyrimidine (71) (2-dmpymoH), and pyrimidine (72) (pym), shown here as the minor tautomer, have provided metallacalixarenes having closer resemblance to classical calixarenes, as compared with those obtained from uracil. The reactions of [(en)M(H20)2KN03)2 (M = Pd and Pt ) with 2-pymoH in water gave tetranuclear metallacalixarenes [(en)Pd(2-pymo-N2 N3)]4(N03)4 (73) and [ en)Ft 2-pjmo-Nl N3MN03)2 (74) (2000IC2301). As compared with uracil-based systems, the appearance of one set of resonances for each of pyrimidine PI, in their IT NMR spectra showed fast... 

A trivial terminology for these products is common. The substances are 5,6-dihydro-6-hydroxy pyrimidines (9) they could be properly cited... 

Several compounds may interfere with nucleic acid metabolism but commonly their effects are secondary to their primary mode of action, for example, the benzimidazoles. Compounds that inhibit nucleic acid biosynthesis directly are either phenylamides, pyrimidines or hydroxy-pyrimidines. Recently, the phenoxyquinolines were identified as exhibiting a novel mode of action in purine biosynthesis and are potentially useful fungicides. 

Soil (diazinon, diazoxon, 2-isopropyl-4-methyl-6-hydroxy-pyrimidine)... 

Extraction of soil with hexane acetone (1 1), centrifugation, separation of hexane from acetone/water layer. Extraction of acetone/water phase with chlorofornrdiethyl ether (1 1), solvent exchanged to methanol. Hexane layer contained diazinon, chloroform/diethyl ether fraction contained 2-isopropyl-4-methyl-6-hydroxy-pyrimidine. 

Col microscopic ndls, decomp above 300° without melting. Can be prepd by treating an alkaline aq soln of 2,4,5 triamino-6-hydroxy-pyrimidine with NaNOa + AcOH(Ref 2). Prepn of its hydrochloride is described in Ref 3, which also gives the UV absorption spectra Refs l)Beil — not found 2)R.O.RobIin et... 

An early unequivocal synthesis of (11) which, however, is too involved to be practical, involved condensation of 2-amino-4-chloro-5-phenyIazo-6-hydroxy-pyrimidine with the ethylene ketal of aminoacetone, followed by reduction of the phenylazo group, hydrolysis and cyclization to 6-methyl-7,8-dihydropterin. This latter intermediate was then oxidized with potassium permanganate to 6-methylpterin, which was converted to (11) with selenium dioxide in acetic acid (63% in the last step) [36] (Scheme 3.1). 

Although transhalogenations have not found major application to the preparation of chloropyrimidines, the conversion of 5-bromo-6-hydroxy-pyrimidin-4(3//)-one into the 5-chloro derivative by warming with HC1 in dimethylformamide provides the best route to that derivative (64JGU3908). 

Dimethyl-4-hydroxy-pyrimidin und Kaliumcarbonat XII/2, 642 4-(Diethoxy-thiophosphoryloxy)-2-isopropyl-6-methyl- E2, 701... 

Hydro xypyrimidine and 4-hydroxy pyrimidine, which exist predominantly as tautomers [135] and [136] (Gronowitz and Hoffman, 1960), become monoprotonated in trifluoroacetic acid on... 

Other Ditungsten(II) Complexes. The 2-oxopyridine type ligand I, and related monoanionic ligand bridges such as 2-amino-6-methylpyridine and 2,4-dimethyl-6-hydroxy-pyrimidine have played an important role in the development of the chemistry of quad-... 

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