Piromidic acid

Chemical Name 8-Ethyl-5,8-dihydro-5-oxo-2-(1 pyrrolidinyl)pvrido[2,3-d]pyrimidine-6-carboxylic acid 

Trade Name Manufacturer Country Year Introduced 

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This representation is intended to encompass 4-oxo-3-quinolinecarboxyhc acids as well as the corresponding 1,8-naphthyridines, cinnolines, and pyrido[2,3-<55pyrimidines. These classes are illustrated by ciprofloxacin [85721-33-1] (2) (1), naUdixic acid [389-08-2] (3) (2), cinoxacin [28657-80-9] (4) (3), and piromidic acid [19562-30-2] (5) (4), respectively. 

The 4-piperazinyl nitrogen in pipemidic acid (69) has been alkylated, acylated and sulfonylated in the search for enhanced antibacterial activity, whilst the 3-pyrrolidinyl position in piromidic acid (68) is hydroxylated metabolically and enzymically to (74) (75MI21503), from which acyloxy derivatives have been prepared. 

In the 2-position, the methylthio derivatives have mostly been used, especially in the synthesis of piromidic acid, pipemidic acid and their analogues, whilst in the tricyclic series the methylthio derivative (96) was reacted with hydrazine to give the versatile intermediate (97) (79JHC707). 

Pirogli ride Pi relate, 245 Piromidic acid 470 Pirprofen 2, 69 PirquinozoT 243 Pivampicillin 1, 414 Pizoctyline 420... 

Amino-2-methy It hio pyrimidine Pipemidic acid Piromidic acid... 

Diethyl sodium phthalidomalonate Melphalan Diethyl sulfate Aminometradine Etidocaine HCI Fluorouracil Pipemidic acid Piprozolin Piromidic acid... 

Ethoxymethyleneethyl malonate Floctafenine Nalidixic acid Pipemidic acid Piromidic acid Rosoxacin... 

BHA, BHT, PG, TBHQ and tocopherols) a variety of stationary phases, mobile phases and detectors can be used [711]. Common antibacterials such as carba-dox, thiamphenicol, furazolidone, oxolinic acid, sul-fadimethoxine, sulfaquinoxaline, nalidixic and piromidic acid can be analysed by GE-RPLC-UV (at 254 nm). Collaborative studies have been reported for the HPLC determination of the antimicrobial sodium benzoate in aqueous solutions [712], Plastics devices used for field collection of water samples may contain polymer additives (such as resorcinol monobenzoate, 2,4-dihydroxybenzophenone or bisphenol A) or cyanobac-terial microcystins [713],... 

R= pyrrolidino Piromidic Acid R = piperazino, Pipemidic Acid... 

In contrast to these examples, the antibacterial agent piromidic acid (5.91, Fig. 5.24) is not converted to a lactam derivative but yields only the cw-ami-no acid derivative [188]. Steric features might underlie this metabolic difference. Bulky groups in close proximity to the N-atom seem to favor the formation of the amino acid metabolite, whereas substrates with an unhindered N-atom seem to favor the formation of a lactam metabolite. 

Fig. 5.24. Metabolism of the pyrrolidine ring according to the mechanism in Fig. 5.23. Nicotine (5.86), tremorine (5.89), and prolintane (5.90) are metabolized to both lactam and co-ami-no acid derivatives [185-187]. Due to steric hindrance next to the N-atom, piromidic acid (5.91) yields only the amino acid derivative [188]. 

Six-membered azaheterocycles (i.e.,piperidino derivatives) show a metabolic pattern similar to that of pyrrolidine compounds. Thus, the antiemetic drug diphenidol (5.97, Fig. 5.26) and DN-9893 (5.73) are both metabolized to their co-amino acid and lactam derivatives [177]. In contrast, no lactam metabolite was detected for phencyclidine (5.98, Fig. 5.26), a potent analgesic also widely abused [190]. One may assume that, like for piromidic acid (5.91, Fig. 5.24), steric hindrance at the N-atom is unfavorable for the formation of lactam metabolites. 

Y. Sekine, M. Miyamoto, M. Hashimoto, K. Nakamura, Metabolism of Piromidic Acid A New Antibacterial Agent. II. In vitro Metabolic Pathway of Piromidic Acid in Rats , Chem. Pharm. Bull. 1976, 24, 437-442. 

Pirbuterol, 280 Piromidic acid, 470 Pirprofen, 69 Pizotifline, 420 Poldine, 74... 

Oxolinic acid, nalidixic acid, piromidic acid... 

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