Papaverinic acid

Papaverinic acid, CieHjjO N. HjO, crystallises in small tablets, m.p. 233°. It is dibasic, readily forms an anhydride, furnishes an oxime and a phenylhydrazone, contains two methoxyl groups, and on oxidation yields veratric and pyridine-2 3 4-tricarboxylic acids, and hence is represented by the following formula —... 

Permanganate oxidation of papaverine in neutral medium furnishes m-hemipinic acid (V), veratric acid (VI), papaverinic acid (a-veratroylcincho-meronic acid) (VII), and pyridine-2,3,4-tricarboxylic acid (VIII). The last-named product (VIII) may serve as evidence for the point of attachment of the nitrogen-free portion of the isoquinoline system. Dimethoxy-isoquinolines are oxidized to pyridine-3,4-dicarboxylic (cinchomeronic) acid, but papaverine yields VIII under analogous conditions, thus marking position 1 as the connecting point. 

CgHjoO,. A compound of largely historical interest for its role in establishing the structure of many natural products. Methylation of vanillin gives veratraldehyde which may be oxidized to veratric acid. Veratric acid was identified as a degradation product of the alkaloid papaverine. 

Papaverine, C20H21O4N. This alkaloid, first obtained by Merck, occurs in the mixture precipitated by ammonia from the mother liquors of opium extract from which morphine and codeine have been separated in Gregory s process, and methods for its isolation from this mixture have been published by Hesse and others. The alkaloid may be purified by conversion into the acid oxalate, B. H2C2O4, m.p. 196° or 201-5-202°, which is nearly insoluble in alcohol. 

In this, the first serious and successful work on the structure of a complex alkaloid, there was naturally at first some confusion between Moquinoline and the better-known quinoline. The 6 7-dimethoxy-woquinolinecarboxylic acid was thought to be a dimethoxycinchoninic acid. It known, however, that quinoline benzylchloride on oxidation furnished formylbenzylanthranilic acid, CjH4(COOH)—N(C,H,)—CHO, whereas various papaverine alkyl halides gave what were presumed to be... 

The position in which the veratryl residue is attached to this isoquinoline nueleus in papaveraldine and papaverine is determined by the formation of pyridine-2 3 4-tricarboxylic acid in the oxidation of papaverine by hot permanganate. On the basis of these results, Goldschmiedt assigned the following formula to papaveraldine —... 

The constitution of laudanosine was determined by Pictet and Athanasescu/ who prepared it by reducing papaverine methochloride with tin and hydrochloric acid and deracemising the dZ-laudanosine (iV-methyltetrahydropapaverine) so obtained, by fractional crystallisation of the quinate. Laudanosine must, therefore, be represented by formula... 

The cyclization reaction of some substituted 1,2-dihydroisoquinolines is of interest (255). The reduction of papaverine with tin and hydrochloric acid affords the 1,2-dihydro compound in the form of immonium salt 172, which then undergoes a cyclization reaction in the acidic medium to give compound 173, called pavine (257). 

On treatment of N-methylpapaverine, formed by the lithium aluminum hydride reduction of papaverine methiodide with phosphoric acid, N-methylpavine is formed which is identical with the racemic alkaloid argemonine. This reaction was used for the synthesis of the alkaloid (-h)-coreximine (268) (174) and similar compounds containing the proto-berberine grouping in the molecule (269,270). 

Paludrine 1, 115 Pamaquine 1, 345 Pamatolol T, 28 Pancuronium chloride 163 Papaverine 1, 347 Para-aminosalicylic acid J, ... 

To 3,65 g (0X)1 mol) of monohydrated adanosine-5 -monophosphoric acid,brought into suspension in a mixture of 45 ml of water and 5 ml of ethanol, are added 3.39 g (0.01 mol) of papaverine base (melting point, 147°C). The mixture Is gently heated until a final temperature of 40°C is reached. The solution obtained is then filtered and the filtrate is concentrated under vacuum. The remaining product quickly crystallizes. After drying to 50°C to constant weight, there are obtained 6.68 g of desired product, in the monohydrated state, as a white crystalline powder, which melts at 140°C and is very soluble in water. 

Adenosine-5 -monophosphoric acid Papaverine monophosadenine Adipic acid dichloride lodipamide Adrenalin... 

C5H12N2 505-(56-S) see Fasudil homoveratric acid (C10H12O4 93-40-3) see Papaverine homoveratronitrile... 

Irreversible reaction of [18] iodine with acetylsalicylic acid, aethaverine, amidopyrine, ascorbic acid, benzo-caine, quinine, dihydrocodeine, fluorescein, glycine, hydrocortisone acetate, isoni-azid, metamizole, papaverine, paracetamol, phenacetin, phenol-phthalein, piperazine, resorcinol, salicylic acid, salicylamide, sulfaguanidine, thymol, triethanolamine, tris buffer detection by reaction chromatography... 

The opiate alkaloid, papaverine, from Papaver somniferum is an anti-spasmodic, vasodilator, and smooth muscle relaxant. Its total synthesis has been studied since Pictet and Gams early work in 1909 and has since been followed up by various industrial syntheses up till the early 1950s using important industrial commodities as vanillin, acetovanillone, veratraldehyde (methylvanillin), and homoveratric acid as starting materials (see Figure 4.50). Table 4.23 summarizes the results of the five synthetic plans for this natural product. All are convergent... 

The convective diffusion approach for weak basic drugs dissolving in acidic media was previously derived by Litt and Serad [9] and, as shown by McNamara and Amidon, could be applied to dissolution of the free base of papaverine. 

This approach was followed by Yushmanov for the localization of papaverine in ionic micelles.42 Another interesting application was reported by Chien43 who measured 19F NMR relaxation times of trifluor-omethyl labelled atrazine induced by paramagnetic probes gadolinium ethylenediamine tetraacetic acid and 2,2,6,6-tertramethyl-piperidine-N-oxyl. The results showed that atrazine solubilized by humic micelles occupied a hydrophobic domain accessible only to neutral hydrophobic molecules. 

PAG , 111 Paludrine, 115 Pamaquine, 345 Papaverine, 347, 348 Para-aminobenzoic acid, in bacterial metabolism, 109, 121 Para-aminosalicylic acid, 109 Paraethoxycaine, 10, 11 Paramethadione, 232 Paramethasone, 200 Parasympathetic nervous system, 35, 62... 

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