Heterocyclics INDEX

The ancient Egyptians used the plantAmmi majus, which contains methoxsalen (sometimes called 8-methoxypsoralen, based on a now obsolete method of naming fused heterocycles indexed in Chemical Abstracts under furo[3,2-g][l]benzopyran-7-one, 9-methoxy-, 249), in combination with sunbathing to... 

Theoretical and structural studies have been briefly reviewed as late as 1979 (79AHC(25)147) (discussed were the aromaticity, basicity, thermodynamic properties, molecular dimensions and tautomeric properties ) and also in the early 1960s (63ahC(2)365, 62hC(17)1, p. 117). Significant new data have not been added but refinements in the data have been recorded. Tables on electron density, density, refractive indexes, molar refractivity, surface data and dissociation constants of isoxazole and its derivatives have been compiled (62HC(17)l,p. 177). Short reviews on all aspects of the physical properties as applied to isoxazoles have appeared in the series Physical Methods in Heterocyclic Chemistry (1963-1976, vols. 1-6). 

This index lists the text pages on which quantitative information can be found relating to over 4000 specific heterocyclic compounds. In general the technique used (eg. H NMR) to measure the information has been given and not the type of information provided (eg. chemical shift values). The latter details may be found on the text pages themselves. 

This index contains over 40,000 individual entries to the 6200 text pages of Volumes 1-7. The index mainly covers general classes of heterocyclic compound and specific heterocyclic compounds, but also included are natural products, other organic and organometallic compounds where their synthesis or use involves heterocyclic compounds, types of reaction, named reactions, spectroscopic techniques and topics involving heterocyclic compounds. 

The Subject Index of over 20 000 entries has been compiled from keywords, names and formulae in the text and tables. It covers general classes of compound, specific compounds, general types of reaction, specific and named reactions, spectral and other properties, and other topics in heterocyclic chemistry. More details are again given at the beginning of the index in Volume 8. 

Index entries are divided into two categories, primary and secondary. Primary index entries are used when a significant part of the text is devoted to a particular ring system this may be a whole chapter, or a section or subsection. Secondary index entries are used when a heterocyclic system is mentioned in a chapter devoted to another (primary) system. This may be, for example, as a starting material or as a product, or in a discussion comparing properties. 

This review includes most of the published articles from the defined area and excludes only imidazoquinolines, which were reviewed in Weissberger-Taylor s series The Chemistry of Heterocyclic Compounds (81MI1). Comprehensive Heterocyclic Chemistry II (96MI1) mentioned only some of the azoloquinolines in the first edition the authors omitted citations about this type of compounds. The trend toward interest in these compounds can be illustrated by the number of citations in Chemical Abstract as shown in Table I. Besides Chemical Abstracts Substance/Subject (Collective) Indexes, the MDL database search has been used. 

As an index volume, Volume 80 of Advances in Heterocyclic Chemistry also includes cumulative indexes of authors and titles of chapters in volumes 1 through 80 of the series together with a cumulative subject index for volumes 76 to 80. Previous cumulative subject indexes have appeared in volumes 60, 70 and 75. 

Volume 85 of Advances in Heterocyclic Chemistry comprises three chapters and indexes. 

The order of aromaticity of these compounds is benzene > thiophene > pyrrole > fiiran, as calculated by an aromaticity index based on bond-distance measurements. This index has been calculated for five- and six-membered monocyclic and bicyclic heterocycles Bird, C.W. Tetrahedron, 1985, 41, 1409 1986, 42, 89 1987, 43, 4725. 

Another publication is the Index of Reviews in Organic Chemistry , complied by Lewis, Chemical Society, London, a classified listing of review articles. The first volume, published in 1971, lists reviews from 1960 (in some cases much earlier) to 1970 in alphabetical order of topic. Thus four reviews are listed under Knoevenagel condensation , five under Inclusion compounds , and one under Vinyl ketones. There is no index. A second volume (1977) covers the literature to 1976. Annual or biannual supplements appeared from 1979 until the publication was terminated in 1985. Classified lists of review articles on organometallic chemistry are found in articles by Smith and Walton and by Bruce.A similar list for heterocyclic chemistry is found in articles by Katritzky and others.See also the discussion of the Index of Scientific Reviews, page 1638. 

Comprehensive Organic Chemistry , Pergamon, Elmsford, NY, 1979, is a six-volume treatise on the synthesis and reactions of organic compounds. The first three volumes cover the various functional groups, vol. 4, heterocyclic compounds, and vol. 5, biological compounds such as proteins, carbohydrates, and lipids. Probably the most useful volume is vol. 6, which contains formula, subject, and author indexes, as well as indexes of reactions and... 

As 1,2,5-thiadiazole analogues, potent HlV-1 reverse transcriptase inhibitors, some simple 1,2,5-oxadiazoles, compounds 4-6 (Fig. 9), have been synthesized using the traditional Wieland procedure as key for the heterocycle formation [121]. Such as thiadiazole parent compounds, derivative with chlorine atoms on the phenyl ring, i.e., 5, showed the best anti-viral activity. Selectivity index (ratio of cytotoxic concentration to effective concentration) ranked in the order of 5 > 6 > 4. The activity of Fz derivative 6 proved the N-oxide lack of relevance in the studied bioactivity. These products have been claimed in an invention patent [122]. On the other hand, compound 7 (Fig. 9) was evaluated for its nitric oxide (NO)-releasing property (see below) as modulator of the catalytic activity of HlV-1 reverse transcriptase. It was found that NO inhibited dose-dependently the enzyme activity, which is hkely due to oxidation of Cys residues [123]. 

One may consider phospholes to belong to the family of five-membered P-heterocycles pyrrole, furan, and thiophene. A significant difference, however, is that the phospholes described in the literature display only a slight extent of aromaticity. This is well demonstrated by the comparison of the Bird-indexes [32] of benzylphosphole [33], furan, pyrrole, and thiophene (Fig. 1). The Bird-index is an indicator of aromaticity based on the bond-equalizaton. It is the maximum (100) for benzene. 

Fig. 1 The aromaticity of five-membered heterocycles characterized by the Bird-Index [32]...

Information about membership and activities of the International Society of Heterocyclic Chemistry (ISCH) can be found on the World Wide Web at http //webdb.uni-graz.at/ kappeco/ISHC/index.html... 

This index lists the heterocyclic parent ring systems and has been compiled from the occurrences of those systems and their derivatives in Volumes 1-15 in the text, tables, equations, and schemes. Heterocycles have been included when they occur as a starting material, isolable intermediate, or a product, but not when they are reported as a nonisolable intermediate or a solvent. 

Compounds are generally classified according to their fully unsaturated parent compound (but see below). Thus substituted, partially saturated, and fully saturated derivatives of, for example, pyrrole are all indexed under pyrrole. Benzo and similar derivatives are included under the most unsaturated parent system (e.g., quinoline, thienofuran, etc.). For any given heterocyclic parent only one indicated hydrogen isomer appears in the text, typically the most stable or the lowest numbered form thus all instances of pyran, whether of the 2H- or 4H-form, are indexed under 2H-pyran. The charges and additional valences for any heterocyclic parent structure are not indicated. 

The overall style follows that used in Chemical Abstracts and the first two editions of Comprehensive Heterocyclic Chemistry, but in order to keep the size of the index within reasonable bounds more attention has been paid to the monocyclic and bicyclic rings and only systems containing up to six fused rings have been included. For the same reason a limit on individual ring size in any system has been placed at 12 atoms. Also complexes of metals, clusters and carcass structures are not included. 

There are little data on theoretical chemistry associated with such ring systems. In a series of 5,5-fused heterocycles, the inner salt 1 displays a substantial aromatic character as indicated by the aromaticity index 7(5,5) with a value of 82 <1987T4725>. 

Dyes in this category, classified as methines (1.21) and polymethines (1.22) in the Colour Index, characteristically contain a conjugated system through one or more methine (-CH=) groups terminating with heterocyclic atoms, usually nitrogen as in the quinoline (1.21) and... 

Besides the applications of the electrophilicity index mentioned in the review article [40], following recent applications and developments have been observed, including relationship between basicity and nucleophilicity [64], 3D-quantitative structure activity analysis [65], Quantitative Structure-Toxicity Relationship (QSTR) [66], redox potential [67,68], Woodward-Hoffmann rules [69], Michael-type reactions [70], Sn2 reactions [71], multiphilic descriptions [72], etc. Molecular systems include silylenes [73], heterocyclohexanones [74], pyrido-di-indoles [65], bipyridine [75], aromatic and heterocyclic sulfonamides [76], substituted nitrenes and phosphi-nidenes [77], first-row transition metal ions [67], triruthenium ring core structures [78], benzhydryl derivatives [79], multivalent superatoms [80], nitrobenzodifuroxan [70], dialkylpyridinium ions [81], dioxins [82], arsenosugars and thioarsenicals [83], dynamic properties of clusters and nanostructures [84], porphyrin compounds [85-87], and so on. 

Chatteijee, A., Ebina, T., and Iwasaki, T. 2001. Best dioctahedral smectite for nitrogen heterocyclics adsorption—A reactivity index study. J. Phys. Chem. A 105 10694-10701. 

P.O.67 is a member of the pyrazolo-quinazolone pigment series. Its constitution is listed in the Colour Index under Constitution No. 12915. Coupling component is the heterocycle shown on p. 503. The diazonium component is 2-nitro-4-chloroani-line. Coupling affords the pigment, which was found to exhibit the hydrazone structure ... 

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