Diamino-6-hydroxypyrimidine

Recently it was discovered that cofactor activity with phenylalanine hydroxylase is not limited to tetrahydropterin derivatives. Thus, the substituted pyrimidines 2,4,5-triamino-6-hydroxypyrimidine (21) and 5-(benzylamino)-2,4-diamino-6-hydroxypyrimidine (22) are active in the L-phenylalanine hydroxylating system (78BBR(85)1614, 79JBC(254)5150, 80JBC(255)7774). The amine substituent at C-5 of (21) and (22) is apparently required for... 

A Princeton group announced the first synthesis of L-5-deazaFA (91) via a path which to date remains the shortest and most direct route to this series [79, 80], In one step, reaction of 2,4-diamino-6-hydroxypyrimidine (87a) with purified triformylmethane [81a,b] produced 2-amino-5-deazapterin-6-carbox-aldehyde (88a), which was characterized as the acetamide (89a). Reaction of (89a) with dimethyl p-aminobenzoyl-L-glutamate in glacial HOAc afforded an intermediate imine which was reduced in situ with borane-triethylamine, yielding (90). Saponification of the amide and esters then completed the synthesis of (91) in 62% yield from (88a) (Scheme 3.18). Adaptation of this... 

Heterocycles as Coupling Components. If heterocyclic polyamine coupling components, e g., 2,4-diamino-6-hydroxypyrimidine, are used as coupling components with aromatic diazonium compounds, dyes are obtained that color polyacrylonitrile in lightfast yellow shades and are characterized by excellent leveling properties [5], An example is 1 [6979-64-2],... 

Heterocyclic coupling components that have been coupled with diazotized ami-nophenyltrimethylammonium chloride are l-alkyl-6-hydroxy-2-pyridone [93], 1-amino-3-hydroxy-isoquinoline [94], and 2,4-diamino-6-hydroxypyrimidine [95], The trialkylammoniumaryl residue may also be connected to the aromatic diazo component via a sulfone or a sulfonamido function [96], Disazo dyes in this series (e.g., 34) [77901-21-4] may also be generated from monoazo dyes that still contain a primary amino group by dimerization using phosgene [97] or cyanuric chloride [98],... 

Diamino-6-hydroxypyrimidine condenses with nitromalonaldehyde in presence of alkali to give 2-amino-4-hydroxy-6-nitropyrido[2,3-d]pyrimi-dine (100) (75%).92 In a similar reaction 2,4-dioxo-l-hydroxy-6-nitro-lf/,3//-pyrido[2,3-d]pyrimidine is formed (101) [Eq. (32)].93... 

Ethanolic sodium ethoxide is employed also to effect condensation of guanidine (taken as the hydrochloride) with ethyl cyanoacetate to produce 2,4-diamino-6-hydroxypyrimidine. With urea as reactant in place of guanidine, the product is... 

Diamino-6-hydroxypyrimidine, 6R-5,6,7,8-tetrahydro-L-biopterin and L-sepiapterin were potent inhibitors of the recombinant interferon-y-induced production of nitrogen oxides in intact cultured rat alveolar macrophages with I50 values for 6R-5,6,7,8-tetrahydro-L-biopterin and L-sepiapterin of approximately 10 pM (Jorens et al. 1992). 

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