From Big Medical Encyclopedia

NITROFURANS — the chemical compounds having 5-nitrofuran group in the structure; have chemotherapeutic activity. The first connections of this class were synthesized at the end of 19 century, but antibacterial properties for the first time are described only in 1944 by Doddom (M. Dodd), etc. As mother substance for N.'s synthesis use furfural (see). Active N.' most is replaced 5-nitro-2-furfurylidenehydrazone on the chemical structure:

or 5-nitro-2-furil-(beta akriliden) hydrazone:

where R — H; CH 3  ; CH 2 OH; x=O; S; NH; y — different functional groups.

The exception makes Nitrofurylenum, the being N-(5-nitro-2-furyl) - beta nitroethylene.

All N. the fine-crystalline powders having coloring from light yellow to orange-yellow and dark red. Badly rastvorima in water (10 - 5 — 10 - 3 the mol/l), is better — in ethanol, polyethyleneglycol (10 - 3 — 10 - 2 mol/l), it is good — in a dimethyl sulfoxide and dimethyl formamide (to 10 - 1 mol/l). Water solutions H. are quite stable in the neutral and subacidic environment, in alkaline condition decay. Nitrofuran connections are photosensitive. Apply polyarografichesky, spectrophotometric and hromatografichesky methods of the analysis to quantitative definition of N.

The main drugs of a nitrofuran row used in medical practice are Furacilin (see), furagin (see), furadonin (see), furasolidone (see) and Furazolinum (see).

N possess a wide range of antimicrobic action and are active concerning gram-positive and gram-negative bacteria, and also trypanosomes, leptospir, koktsidiya, trichomonads, lyambliya, excite leu of a psittacosis, inguinal lymphogranulomatosis, etc. N. affect strains of microorganisms, steady against antibiotics and streptocides. Concerning viruses H. are inactive. In low concentrations render bacteriostatic, and in higher — bactericidal effect. Medicinal resistance of microbes to N. develops much more slowly, than to the antibiotics applied in practice and does not reach high degree. On an action spectrum separate N. differ from each other a little. E.g., Furacilin affects both on gram-positive, and gram-negative bacteria, furasolidone influences generally gram-negative bacteria, trichomonads and lyambliya. Nek-rye N., napr, Nitrofurylenum, have a fungistasis. Separate N. show antineoplastic activity. So, it is revealed to lay down. effect of Furacilin at a seminoma. Other N. having the following general structure:

where x — geterit, n = 1 or 2, detain growth of a number of experimental tumors. The most active in this series of compounds are nitrofurylvinylpyrimidines and quinolines.

At enteral introduction different N. are soaked up unequally and in unequal quantities are allocated through kidneys. So, at the person with urine furadonin it is emitted in number of 19,1 — 32,6%, furagin — in number of 9,6 — 20,9%, furasolidone — in number of 6,2 — 9,9% and Furacilin — in number of 1 — 3,1% of orally entered dose. In an organism in the course of biotransformation the nitrogroup at a furan ring of N. can be recovered to an amino group owing to what connections lose antimicrobic activity. In the subsequent biotransformation occurs by acetylation of an amino group.

Consider that the mechanism of antimicrobic action of N. is connected with their elektronoaktseptorny properties, than their ability to influence nek-ry enzymatic processes of cellular respiration is caused. So, Furacilin in anaerobic conditions slows down acetylation of KOA and interferes with involvement pyroracemic to - you in a tricarbonic acid cycle.

N appoint hl. obr. outwardly and inside. In surgery, obstetrics, gynecology, ophthalmology and otorhinolaryngology to treatment and the prevention of pyoinflammatory processes of N. apply outwardly in the form of water (Furacilin, furagin, furasolidone) or spirit (Furacilin) solutions, and also ointments and other dosage forms. Inside N. apply at bacterial dysentery (Furacilin, furasolidone), a typhoid, food toxicoinfections of paratyphoid character, a salmonellosis and a lambliasis (furasolidone). At inf. diseases of uric ways (a pyelitis, pyelonephritis, cystitis, an urethritis) are more effective furadonin and furagin. At mecotic colpitises combine topical administration of furasolidone with appointment it inside. For parenteral administration use soluble furagin (a synonym solafur), being potassium salt of a furagin. The drug is administered intravenously kapelno at sepsis, pneumonia and inf. diseases of the uric ways caused by stafilokokka, streptococci, colibacillus and others sensitive to faugh-raginu activators. Or 0,05% of spirit solution apply Nitrofurylenum in the form of ointments (0,05 — 1%) to treatment of an epidermophitia and damages of skin yeast-like fungi.

At external use of N. are usually well transferred. Development of dermatitis is in some cases possible. At intake of N. can make a loss of appetite, sick, vomiting, allergic reactions (a dieback, an enantema). At prolonged use of N. neuralgia and neuritis in this connection it is not recommended to appoint them in more than 10 days are possible. In case of side effects use antihistaminic drugs, vitamins of group B. At the expressed by-effects reduce a dose or stop further administration of drugs. Furasolidone inhibits MAO and therefore can cause the nek-ry by-effects inherent to MAO inhibitors. During administration of drug it is necessary to observe the same precautionary measures, as at reception of antidepressants from group of MAO inhibitors. Besides, furasolidone like Teturamum breaks metabolism of alcohol in this connection the use of alcoholic beverages during treatment by furasolidone can cause the phenomena similar to those, to-rye are observed at alcohol intake against the background of action of Teturamum (face reddening, difficulty of breath, heartbeat, decrease in the ABP).

Contraindications to N.'s use the increased individual sensitivity, a serious illness of heart, liver and kidneys are.

Bibliography: Alekseeva JI. H. Antibacterial drugs — derivatives 5 nitrofurans, Riga, 1963; B of l South of e r A. F. Nitrofurans and them apply ny in medicine, Riga, 1958; And S. A l-ler. Nitrofurans, in book: Questions of use of pentozansoderzhashchy raw materials, under the editorship of P. A. Moshkin, etc., page 451, Riga, 1958; 3 Pi d e r m and N of e A. And. and d river. Antineoplastic activity of derivatives of nitrofuran, Chemical - pharm, zhurn., t. 12, No. 3, page 86, 1978; To r at L. V z-meter. Nitrofuran drugs in fight against a staphylococcal infection, Riga, 1964; Egert V. E., Stradyn I. Item and III and m and Kai M. V. nanosecond. Methods of analytical definition of connections 5-nitrofurano-vogo of a row, Riga, 1968; L about e w e H. Nit-rofuran-derivate, in book: Arzneimittel, hrsg, v. G. E hr h art u. H. Ruschig, Bd 4, T. 1, S. 193, Weinheim, 1972; Miura K. a. Reckendorf H. K. The nitrofu-rans, in book: Progr. med. ehem., ed.

by G. P. Eliis a. G. B. West, p. 320, L., 1967.

A. A. Kimenis.