Heterocyclics phenanthridines

Fluorogenic and chromogenic chemosensors and reagents for anions based on aromatic heterocycles (phenanthridine, calixpyrroles polypyridines, etc.) 03CRV4419. 

Merck Index Number 4769 Chemical/Dye Class Heterocycle Phenanthridine Molecular Formula C2iH2oBrN3 Molecular Weight 394.31... 

Other Names Phenanthridinium, 5,5 -[l, 3-propanediyl-bis-[(dimethyliminio)-3,l-propanediyl]]bis[3,8-diamino-6-phenyl-, tetraiodide EthD 2 Ethidium homodimer 2 Merck Index Number Not listed Chemicai/Dye Class Heterocycle Phenanthridine Molecular Formula C5xH ol4Ns Molecular Weight 1292.71 Physical Form Purple crystals or red solid... 

Diamino-5-(diethylmethylaminopropyl)-6-phenyl-phenanthridinium diiodide Propidium diiodide Propidium iodide PI Merck Index Number Not listed Chemical/Dye Class Heterocycle Phenanthridine... 

Benzo[c]phenanthridine alkaloids are widespread in Papaveraceae, Fumariaceae, and Rutaceae. Fagaridine (118), the structure of which had to be revised, is a derivative of the unknown 5-methyl-benzo[c]phenan-thridine-8-olate (119) which is isoconjugate with the 2-methyl-chrysene anion (Scheme 43). Thus, Fagaridine is a member of class 1 of conjugated heterocyclic mesomeric betaines, which are isoconjugate with odd alternant hydrocarbon anions. 

In this chapter, an attempt has been made to present a total number of 20 QSAR models (12 QSAR models for topo I inhibitors and eight QSAR models for topo II inhibitors) on 11 different heterocyclic compound series (an-thrapyrazoles, benzimidazoles, benzonaphthofurandiones, camptothecins, desoxypodophyllotoxins, isoaurostatins, naphthyridinones, phenanthridines, quinolines, quinolones, and terpenes) as well as on some miscellaneous heterocyclic compounds for their inhibition against topo I and II. They have been found to be well-correlated with a number of physicochemical and structural parameters. The conclusion, from the analysis of these 20 QSAR, has been drawn that the inhibition of topo I is largely dependent on the hydrophobicity of the compounds/substituents. On the other hand, steric parameters (molar refractivity, molar volume, and Verloop s sterimol parameters) are important for topo II inhibition. 

Over the years, many spiropyran structures have been prepared. The pyran component consists of benzopyran or naphthopyran and the heterocyclic part consists of indoline, benzothiazoline, benzoxazoline, benzoselen-azoline, phenanthridine, acridine, quinoline, benzopyran, naphthopyran, xanthene, benzodithiole, benzoxathiole, and saturated heterocyclic rings such as pyrolidine and thiazolidine. 

The photocyclization of enamides has been widely employed in the construction of heterocyclic systems the N-acryloyl-2-aminopyridines 37, for example, are converted on irradiation to the lactams 38.36 Numerous benzylisoquinoline alkaloids have been prepared using this approach, and in particular, the syntheses of benzo[c]phenanthridine alkaloids have been reviewed.37 Thus, irradiation of the [Z]-l-ethylidene-2-benzoyltetra-hydroisoquinoline 39 affords the corresponding 8-oxoberberine 4038 competing photoisomerization to the E-isomer is observed but cyclization occurs only via the Z-isomer. Examples of syntheses of Amaryllidaceae and indole alkaloids have also been reported. In this way, the precursor 41 of ( )-lycoran has been obtained by oxidative cyclization of the enamide 42.39... 

Intramolecular cyclization of 2-lithiobenzyl-2-halophenyl amines, ethers, and thioethers—Synthesis of phenanthridine, dibenzopyran, and dibenzothiopyran derivatives Having demonstrated the efficiency of this methodology for the preparation of indole derivatives, we prepared the 2-fluoro-phenyl ether and thioether 22 a, b to study their potential as substrates that could afford oxygen and sulfur heterocycles. However, treatment of 22 a, b with fBuLi afforded, after... 

L. Walls, Phenanthridine in Heterocyclic Compounds (R. C. Elder-field, ed.) (Russian translation), Vol. 4, p. 430. Inostrannaya Litera-tura, Moscow, 1955. 

The thermolysis of 9-(p-tolyl)-9-azidotelluraxanthene 107 (X = N3) in refluxing xylene leads to ll-(p-tolyl)dibenzo[6/][l,4]tellurazepine 109, the first representative of the previously unknown tellurazepine heterocyclic system (87KGS279). Along with the tellurazepine 109 obtained in rather low (21%) yield, the arylimine 110 and phenanthridine 111 were also isolated as products of the thermolysis in 32% and 20% yield, respectively. 

Phenanthridines are obtained from 2,2 -disubstituted biphenyls in which the substituents react intramolecularly to form the heterocyclic ring. The oldest examples of syntheses of this type involve Hofmann65 and Curtius66- 67 reactions on biphenic acid, and have been explained... 

Loader and Timmons have described a number of photocyclizations which involve coupling with a heterocyclic ring in the presence of atmospheric oxygen. Irradiation of fraras-4-styrylquinoline (122) in hexane or cyclohexane gives 7,8-benzophenanthridine (124).161-163 In the latter solvent a small amount of 6-cyclohexyl-7,8-benzo-phenanthridine, resulting from the photochemical reaction between 7,8-benzophenanthridine and the solvent, has been isolated alkyla-... 

Volume 13 of this serial publication comprises six chapters of which four deal with general accounts of compound classes 1-azirines (F. W. Fowler), phenanthridines (B. R. T. Keene and P. Tissington), tri-thiapentalenes (N. Lozac h), and heterocyclic ferrocenes (F. D. Popp and E. B. Moynahan). The other two chapters are concerned with particular aspects of the chemistry of groups of heterocyeles the tautomerism of purines (B. Pullman and A. Pullman) and quantitative aspects of the electrophilic substitution reactions of five-membered rings (G. Marino). 

The decreasing reactivity of the most familiar aromatic heterocyclic compounds with nucleophilic reagents may be illustrated by the following sequence quinoxaline > acridine > phenanthridine > isoquinoline > quinoline > pyridine. Acridine is alkylated in the 4-position, phenanthridine and quinoxaline in the a-position, isoquinoline in the 1-position, and quinoline and pyridine in the 2- or 4-positions. Weaker nucleophilic reagents seem to enter the 4-position of the pyridine and quinoline rings. If the addition occurs readily and in good yield, the intermediate dihydro derivative may sometimes be isolated otherwise, the product of the subsequent oxidation results. In synthetic work the dihydro derivative is usually directly oxidized. 

Region C Introduction of the dihydroazine moiety into region C derived from the aromatic heterocycles such as phenanthridine, benzo[c]quinoline, quinolines, or isoquinolines and azines increases the ty2 values constantly. In going from left to right, the positive charge in betaine 9 is stabilized more efficiently (Scheme 15). 

Related 1,3-oxazepines have been obtained from irradiation of many other heterocyclic A-oxides including pyridine A-oxides, isoquinoline A-oxides, quinoxaline A-oxides, quinazoline A-oxides, phenanthridine A-oxides, benzophenazine A-oxides, and acridine A-oxides.4 However, the reported yields are variable and have generally been higher for phenyl and other aryl-substituted derivatives. 

By suitable substitution the enaminones can often serve as precursors for heterocycles and preparation of indoles, carbazoles, quinolines, acridines and phenaNthridines can be achieved easily. However, this part of enaminone chemistry can lead to surprising and unexpected reactions if the multifunctional properties of the enaminones are ignored, e.g. ring contraction, ring expansion and other rearrangements are observed. In some cases jft-ketoenamines react as the ene-component in cycloaddition. Enaminones are even suitable synthones for building aromatic rings. 

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