Phenothiazin-3-ones structure

Phenothiazine derivatives. Comparison of the structures in Scheme 1.37 can lead to a prediction that hexa(anisyl)-l,3,5-triaminobenzene is more similar to 10,10 -(l,3-phenylene) diphenothiazine than to 10,10 -(l,4-phenylene)diphenothiazine. Nevertheless, on one-electron oxidation, these two isomeric diphenothiazines give dication-diradicals (Okada et al. 1996, Sun et al. 2004). As shown, m-phenylenediphenothaizine has a singlet state, and p-phenylenediphenothiazine has a triplet state. Both diphenothiazine dication-diradicals... 

Thioxanthenes differ structurally from phenothiazine in that the nitrogen atom of the central ring of the tricyclic system is replaced by carbon, which is joined to a side chain with a double bond. Their pharmacological action is similar to the corresponding phenothiazine analogues. They have the exact mechanism of action and an analogons effect on the CNS. Drugs of this series differ from one another by quantitative indexes. 

The various topics discussed in this book have up to this point been arranged as far as possible on the basis of chemical structure compounds that contain one oxygen and one nitrogen atom have, for example, as a general rule preceded those that contain two nitrogen atoms. The fact that virtually all of the entities that follow show CNS activity combined with the circumstance that phenothiazines comprise a large part of this section require a departure from that approach. The serendipitous discovery of the antipsychotic activity of the phenothiazines in the early 1950s virtually opened the modern era of medicinal chemistry. These will thus be discussed at the outset to preserve historical perspective. 

The advantage of using free radical inhibitors to facilitate the copolymerization of a bisbenzocyclobutene with a bismaleimide was first noted in a patent to Bartmann [78]. Subsequent to this, Corley in a series of patents described some detailed experiments on the copolymerization of bisbenzocyclobutenes with bismaleimides both with and without the addition of a free radical inhibitor [33, 34]. The structures of the bisbenzocyclobutenes used in this study are shown in Fig. 33. The bismaleimide component that was used was a mixture of three different bismaleimides in the molar ratio shown in Fig. 34. The individual bisbenzocyclobutenes were blended at elevated temperature with varying amounts of the bismaleimide composition. In some of the experiments, the free radical inhibitor phenothiazine was added at a 0.5 mole % level. The various monomer mixtures were then copolymerized using one of the cure schedules described in Table 14. The copolymers were then physically characterized using a variety of techniques. Table 14 shows the results obtained from copolymers... 

Since superoxide reduces readily quinoid structures (e.g. B) (14), product C (7-hydroxy-3H-phenothiazine-3 one) may have a similar genesis, and 7-(10-phenothiazinyl)-3H-phenothiazine-3-one (D) represents one of the many possible recombination products starting from PT . 

One very intriguing work on benz[c]acridines and benzo[a]phenothiazines establishes a connection between their carcinogenicity and radical production (Kurihara et al. 1998). It would be interesting to check for a connection between the carcinogenicity and electron structures of the corresponding cation radicals too. 

A curious case is that of perylene, 23, which takes up 1.512 per molecule50. The spectrum requires five subspectra for a satisfactory fit, three of which are similar to I3. The remaining two subspectra are similar to those of singly bound I2. A structure is proposed in which two I2 molecules are charge-transfer bound to one end of a linear I3 ion, 24. Phenothiazine shows similar behaviour6 the iodine-doped sample appears to contain two I2 molecules and three I3 ions for every five molecules of phenothiazine. 

While artificial photosynthetic mimics come in many manifestations, our efforts have focused predominantly on the class of molecules represented by the structure in Fig. 10.1. These molecules consist of a visible-light-absorbing chromophore in the form of a trisbipyridineruthenium(ll) complex (C) finked by flexible polymethylene chains to one or more electron donors (D) and an electron acceptor (A). The electron acceptor is anAl,W-dialkylated-2,2 -bipyridine (a so-called diquat ) and the electron donors are Al-aUcylated phenothiazines. The diquat type acceptor was chosen because... 

There have been reports of various phenothiazine and phenoxazine anion-radicals which are species which correspond to structure 244 and its substituted derivatives. Thus, reduction of phenothiazin-3-one in... 

The synthesis of some novel fluoro-substituted benzo[a]phenothiazines and their nucleosides as possible antimicrobial agents was reported [196]. 6-(2-Methoxy-5-methyl/2-methoxy-4-chloro-5-methyl-anilino)-9-fluoro-5H-b enzo [ a ] phenothiazine-5-ones/thiones, 12H-benzo [ a ] phenothiazine-5-ols, 5-acetoxy-12H-b enzo [ a ] phenothiazines, 5-methoxy-12H-benzo [ a ]phenothia-zines and nucleosides, viz N-(2,3,5-lri-0-bcnzoyl-f>-D-ribofuranosyl)-6-(2-methoxy-5-methyl/2-methoxy-4-chloro-5-methyl-anilino)-9-fluoro-5-acetoxy benzo[a]phenothiazines and 9-fluoro-5-methoxy benzo[a]phenothiazines, were synthesized and tested for their antimicrobial activity. The structures of novel compounds were proposed on the basis of elemental analyses, IR and and 19F NMR studies. 

There have been reports of various phenothiazine and phenoxazine anion-radicals which are species which correspond to structure 244 and its substituted derivatives. Thus, reduction of phenothiazin-3-one in DMF gives 259 for which hyperfine splittings are indicated in gauss. The assignment of splittings was made following study of halogenated derivatives of 259 and McLachlan MO calculations. Similar anions from phenoxazin-... 

Phenothiazines have a ring structure that contains both nitrogen and sulfur. The phenothiazine three-ring nucleus may have one of three types of side chains—aliphatic, piperidine, or piperazine. The type of side chain dictates the potency and degree of adverse effects of the drug. 

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