Isoniazid

Aminoguanidine, N,N -diaminoguanidine, isonia-zid, hydroxylamine and hydrazine are weak substrates for horseradish peroxidase in the reaction  

In the reaction with hydrogen peroxide [112] the enzyme itself is oxidised and returns to its ground state by oxidising a suitable substrate (reactions [113] and [114]). 

The same compounds inhibited the reaction of Mycobacterium tuberculosis peroxidase-catalase with hydrogen peroxide, and hyroxylamine was found to be a weak substrate for this enzyme (Brimnes et al. 1999). 

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Pharmaceuticals. The tuberculostatic dmg isoniazid [54-85-3] (60), the hydrazide of 4-pyridinecarboxyhc acid, was one of the eadiest hydrazine-based dmgs introduced in the United States. It is made by the reaction of hydrazine and an isonicotinic acid ester (219). 

Rifampicin, the only commercially available ansamacroHde, is manufactured by MerreU Dow under the tradename Rifadin, and by CIBA under the trade name Rimactane. Rifampicin is also suppHed in combination with isoniazid or pyrazinamide [98-96-4]. The rifampicin—isoniazid combination is known as Rifamate (MerreU Dow), Rifinah (MerreU Dow), and Rimactazid (CIBA) the rifampicin—pyrazinamide as Rifater (MerreU Dow). Several other rifamycin derivatives including rifabutin and rifapentine are undergoing clinical studies. 

Monoamine Oxidase Inhibitors. MAOIs inactivate the enzyme MAO, which is responsible for the oxidative deamination of a variety of endogenous and exogenous substances. Among the endogenous substances are the neurotransmitters, norepinephrine, dopamine, and serotonin. The prototype MAOI is iproniazid [54-92-2] (25), originally tested as an antitubercular dmg and a close chemical relative of the effective antitubercular, isoniazid [54-85-3] (26). Tubercular patients exhibited mood elevation, although no reHef of their tuberculosis, following chronic administration of iproniazid. In... 

Over 250 analogues of the B vitamers have been reported (11,100). Nearly all have low vitamin B activity and some show antagonism. Among these are the 4-deshydroxy analogue, pyridoxine 4-ethers, and 4-amino-5-hydroxymeth5i-2-methyipyrimidine, a biosynthetic precursor to thiamine. StmcturaHy unrelated antagonists include dmgs such as isoniazid, cycloserine, and penicillamine, which are known to bind to pyridoxal enzyme active sites (4). 

Many compounds capable of chelation have been tested for antimicrobial properties. Those showing positive results include saHcylaldoxime [94-67-7] l-nitroso-2-naphthol [131-91-9] mercaptobenzothiazol [149-30-4], dimethylglyoxime [95-45-4], saHcylaldehyde [90-02-8], cupferron [135-20-6], phenanthroline [66-71-7], isoniazid [54-85-3], thiosemicarbazones, the sulfur analogue of oxine, and numerous antibiotics (qv) including tetracyclines. Whether these compounds function exclusively, partially, or at all by virtue of their abiHty to chelate is open to debate. 

Dipping solution Dissolve 1 g isonicotinic acid hydrazide (4-pyridinecarboxylic acid hydrazide, isoniazide) in 100 ml ethanol and add 500 gl trifluoroacetic acid [1] or 1 ml glacial acetic acid. 

Substitution of an amino group into the molecule affords an iigent with antibacterial activity. Although seldom used alone, l, ira- aminosalicylic acid (PAS, 7) has been employed as an adjunct Id streptomycin and isoniazid in treatment of tuberculosis. 

Control of tuberculosis, long one of the scourges of mankind, began with the introduction of effective antibacterial agents. Thus, this disease was treated initially with some small measure of success with various sulfa drugs the advent of the antibiotic, streptomycin, provided a major advance in antitubercular therapy, as did the subsequent discovery of isoniazid and its analogs. 

Thus, condensation of isoniazide with acetone at the basic nitrogen gives the corresponding Shiff base (8). Catalytic reduction affords the antidepressant, iproniazid (9). Addition of the same basic nitrogen to methyl acrylate by Michael condensation leads to the 3-amino ester (10). This is converted to the amide, nialamide (11), on heating with benzylamine. 

Methyl acrylate, 28.0 g (0.4 mol) was added dropwise during one hour to a solution containing 54.8 g (0.4 mol) of isonicotinic acid hydrazide (isoniazid) and 10 ml of glacial acetic acid in 400 ml of tertiary butyl alcohol. The resulting solution then was heated for 18 hours on a steam bath. Concentration of the reaction mixture to 100 ml yielded 13.0 g of unreacted isonicotinic acid hydrazide. The filtrate was concentrated to a thick syrup which was triturated... 

Dow-lsoniazid Isoniazid Dowmycin - Erythromycin Dow-Sulfisoxazole - Sulfisoxazole Doxal - Doxepin HCI Doxaprii - Doxapram HCI Doxedyn - Doxepin HCI Doxergan - Dxomemazine Doxidan Docusate calcium Doxi-OM - Dobesilate calcium Doxitard -Doxycycline Doxium - Dobesilate calcium Doxy - Doxycycline Doxy 200 - Doxycycline Doxylin - Doxycycline Doxy-Puren - Doxycycline Doxyremed - Doxycycline Doxytrex - Dobesilate calcium... 

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