2-Amino-3-methyl pyridine

Fig. 3. Stepwise synthesis of rifaximin (from De Angelis [39]). The reaction of rifamycin S (I) with pyridine perbro-mide (II) in 2-propanol/chloroform (70/30) mixture at 0°C gives 3-bromorifamycin S (III), which is then condensed with 2-amino-4-methyl-pyridine (IV) at 10°C. The o-quinonimic compound (V) is then obtained. This compound is finally reduced with ascorbic acid to rifaximin. 

Amino-4-methyl-pyridine, NOS inhibitor with analgesic activity [695-34-1]... 

The combined liquors, which comprise an aqueous hydrochloric acid solution of 3-amino-methyl-pyridine hydrochloride, are then heated to a temperature of 60° to 65°C, and ethyl nitrite gas is passed into the heated solution. The ethyl nitrite is generated by placing 20 liters of 90% ethyl alcohol in a suitable vessel, diluting with 200 liters of water, and, while stirring, adding to the dilute alcohol 18.3 kg of nitrosyl chloride at the rate of 2.25 kg per hour. (The process using methyl nitrite is carried out by substituting a stoichiometrically equivalent quantity of methyl alcohol for the ethyl alcohol.)... 

Two new Hg(n) and Cd(n) perchlorate complexes of 2,6-bis([(2-pyr-idylmethyl) amino]methyl)pyridine, [HgL(Cl04)2] and [CdL(Cl04)2] have been isolated by Bebout and co-workers as bicapped distorted square pyramidal racemates the structures of both these compounds have been extensively studied by the use of heteronuclear couplings, VuHg and %cd, respectively. 

Here again the question of reactive species in the acidic medium remains open. It must be noted that bromination of 2-amino-5-methyl-pyridine (pK = 7) and 2-amino-5-nitropyridine (pJC = 2.8) in N sulfuric acid takes place on the free base (443). 

The indirect deactivation in 2-amino-4-chloroquinoline (187) requires vigorous conditions (potassium hydroxide in hot ethylene glycol, or boiling propanolic propoxide for 16 hr) to displace the chloro group, which is stable to aqueous alkali and to hydriodic acid. The direct deactivation in 5-amino-2-chloro-3-cyano-6-methyl-pyridine (188) prevents reaction with alkoxide ion under conditions which produce smooth reaction of the des-amino analog. 

Zhang Y, Adachi M, Zhao X, Kawamura R, Imai K (2004) Histone deacetylase inhibitors FK228, N-(2-aminophenyl)-4-[N-(pyridin-3-yl-methoxycarbonyl)amino-methyl]benzamide and m-carboxycinnamic acid bis-hydroxamide augment radiation-induced cell death in gastrointestinal adenocarcinoma cells. Int J Cancer 110 301—308... 

Ceftazidime Ceftazidime is l-[[7-[[(2-amino-4-thiazolyl)[(l-carboxy-l-methylethoxy) imino]acetyl]amino]-2-carboxy-8-oxo-5-thia-l-azabicyclo[4.2.0]oct-2-en-3-yl]methyl]pyridin-2-carboxylic acid (32.1.2.82). As is the case in synthesis of ceftriazone, the synthesis of ceftazidime requires the preliminary synthesis of two starting compounds. 7-Amino-3-(l-pyridinomethyl)cef-3-en-carboxylic acid dihydrochloride is used... 

For exchange in dibasic compounds, such as aminopyridines, ideally if both equilibrium and kinetic protonations follow H0, a rate profile of the type in Figure 3 should be expected (67JCS(B)1219>. Rate profiles obtained for 4-amino, 4-amino-2,6-dichloro- and 2-amino-5-methyl-pyridine correspond to the portions b-c, c-d and d-e respectively of Figure 3. 

Analog erhalt man u.a. aus 4-(Amino-hydroximino-methyl)-pyridin 3-( 4-PyridylJ-l, 2,4-oxadiazol (16% Schmp. 144-147°). 

Amino-hydroximino-methyl)-pyridin liefert mit Dimethylamino-trichlor-methan beim Sie-den in Acetonitril 5-Dialkylamino-3-(2-pyridyl)-l,2,4-oxadiazol (29% Schmp. 82—85°)113 ... 

Propionitrile, 51 -Propylacetylene, 17 2,3-Pyrazinedicarboxylic acid, 86 Pyridine, 3-amino, 3 Pyridine, 5-ethyl-2-methyl, 41 Pyruvic aldehyde-sodium bisulfite, 88... 

The oxidative desulfurization-fluorination of methyl A,-alkyl-A,-pyridyl(or pyrimidin-yl)dilhiocarbamates produces the corresponding (trifluoromethyl)amino-substituted pyridines (or pyrimidines) 5.69... 

A rather different study of the kinetics of decomposition of solid complexes of [VO(dbm)2(L)] (dbm = dibenzoylmethanato, L = py and several methyl-, dimethyl- and amino-pyridines) used differential scanning calorimetry (DSC).531 Using the temperature that corresponds to the loss of the molecule L in equation (37), a linear relationship was found between it and the basicity of L, except for 4-amino- and 4-methyl-pyridine. 

Pyridine forms 3-acetoxymercuripyridine (121) (Hg(OAc)2 -H20, 155°C) 2-amino- and 4-methyl-pyridine give the 5- and 3-acetoxymercuri compounds, respectively, at somewhat lower temperatures. Mercuric acetate mercurates 4-pyridone in the 3-position and 3-hydroxypyridine in the 2-position. 

According to Chuiguk and Oksanich13 the reaction of 2-aminopyridinium perchlorates and /i-chlorovinylaldehydes led exclusively to the 4-substituted products (9) whereas from 2-amino-6-methylpyridine no cyclic product was obtained. With //-chlorovinyl ketones both the 2- and 4-substituted pyrido-[l,2-u]pyrimidinium salts were detected by H NMR.3 2-Amino-6-methyl-pyridine gave rise only to the 2-substituted isomer (10). 

When the 5-phenyl derivative of 43 was used, a mixture of 3-(2-phenyl-2-chloroethyl)- and 3-(2-phenylvinyl)-8-methyl-4-oxo-4H-pyrido[l,2-a]pyri-midines was obtained.49 Depending on the conditions, reaction of 2-aminopyridines with 2-acetyl-4-chloromethylbutyrolactone (47) led to a variety of bicyclic products (48-54) (Scheme 2)49,83 Reaction of 2-aminopyridines with the acid chloride (55) yielded 4-oxo-4H-pyrido[l,2-a]pyrimidines (56) and traces of the amides of type 57. From 2-amino-6-methyl-pyridine, only the amide (57 R = 6-Me) was formed.86... 

Allen et til.90 suggested that 2-aminopyndine and 2-amino-3-methyl-pyridine reacted with diketene in ether to give 2-acetylacetamidopyridine (38 R = H, 3 = Me). Later Shur and Israelstam41 demonstrated that the product formed from 2-amino-3-methylpyridine was in fact 2,9-dimethyl-4-oxo-4/i-pyrido[l,2-a]pyrimidine (41 R = 9-Me). 

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