Indeno structures

Chemical Name 2,3,4,9-tetrahydro-2-methyl-9-phenyl-1 H-indeno[2,1, c] pyridine tartrate Common Name 2-methyl-9-phenyl-2,3,4,9-tetrahydro-Tpyridindene tartrate Structural Formula CcH, ... 

A series of indeno[l,2-c]isoquinolines have been described [27] and INO-lOOl has been investigated in the clinic. Although the structure of INO-lOOl has not been reported, sulfonamide 28 is a representative structure (IC50 = lnM, EC5O = 10nM). CEP-9722 is in Phase I clinical trials, while its exact structure has not been disclosed, it is a prodrug of CEP-8983 (29) and patent applications highlight 30. Preclinical efficacy in combination with TMZ and camptothecin have been... 

SCHEME 3.43 Chemical structures of indeno[l,2,3- /]perylene and its derivatives. 

An Italian team reported that pyridazinones (89) hydroxymethylated at C-5 induced a high decrease in systolic blood pressure in rats [371]. In Italy, much effort has been devoted also to the preparation of conformationally restricted congeners of antihypertensive pyridazinones. In a structure-activity study, it has been found that indeno[l,2-c]pyridazinones, in particular compounds (90), are potent antihypertensive agents [372]. 

The synthesis of a new class of compounds possessing the general structure 4,4,8,8-tetraalkyl-2,3 6,7-dibenzo-9-azabicyclo[3.3.1]nonane-l,5-diol (84) deserves mention since the basic skeleton is analogous to that of the pavines (Scheme 12) (124-129). Oxidation of a series of indeno[2,l-a]indenes 82 with chromic acid yielded dibenzocyclooctanediones 83. Treatment of these diketones with various amines resulted in a transannular reaction to afford species 84 in good yields. 

B. Testa, Inhibition of monoamine oxidase-B by 5H-indeno[1,2-c]pyridazines Biological activities, quantitative structure-activity relationships (QSARs) and 3D-QSARs, J. Med. Chem. 38 (1995) 3874-3883. 

Adapted from Mackay et al. (1992) data on indeno[l,2,3-a/]pyrene from Harvey (1997). Structures and their numbering are based on IUPAC recommendations as described by Loening et al. (1990). h U.S. EPA (1998) designation. Exceptions are noted by asterisks. 

H-chromene synthesis from, 3, 767 Indenobenzazepines pharmacological properties, 7, 546 Indenone oxide, 2,3-diphenyl-photochromic compound, 1, 385 Indeno[ 1,2-e][ 1,2,4]triazines synthesis, 3, 434 Indicated hydrogen nomenclature, 1, 33 Indigo, I, 317, 318-319, 4, 370 Baeyer synthesis, 1, 319 colour and constitution, 1, 344-345 molecular structure, 4, 162 photochromic compound, 1, 386 synthesis, 4, 247 Indigoid dyes... 

In practice, we have utilized it for the analysis of molecular systems comprised of 3 to 5 fused benzene rings. Our discussion in this document is limited to the following compounds phenanthrene, anthracene, fluoranthene, pyrene, benz(a)anthracene, chrysene, benzo(e)pyrene, benzo(a)pyrene, and dibenz(a,h)anthracene. The structures for these compounds are presented in Table I. It is important to note that the method has also been adapted to the determination of several other PAH compounds (e.g., benzo(c)phenanthrene, perylene, 3-methylcholanthrene, carbazole, 7H-dibenzo(c,g)carbazole, and indeno(l,2,3-cd)pyrene). 

Figure 3.15. General structure of an indeno fused naphthopyran.

Dibenzo[b,fjpentalene (indeno[2,la]indene dianion) (32 ) has attracted much interest82). Its preparation via lithium metal reduction of 3 and from 32 by deprotonation with BuLi is very easy. NMR studies ( H, 13C and 7Li) of this system yield information on the electron distribution and the ion pair structure 60,81,82). The intermediate step, i.e. the radical anion 3 affords the estimation of charge densities. The starting material, viz. 3, is a 4nn system and is an excellent example of the Randic approach of polycyclic system s8). The H NMR spectrum of 32 shows the balance... 

The cyclodehydrogenation of electron-rich alkoxy- and alkylthio-substituted hexaphenylbenzenes resulted in ether cleavage [62]. In addition, hexaphenyl-benzenes substituted with redox-active moieties, such as diarylamines or pyridine, do not provide the desired HBC derivatives, presumably due to the preferential formation of nitrogen-localized radical cations [63]. Thus, the hexaether 15 did not yield the desired hexaalkoxy-substituted HBC upon treatment with FeCh, but rather an unexpected indeno[l,2-b]fluorene derivative 16, the structure of which was confirmed using X-ray crystallography (Scheme 13.5) [64]. 

Recently, Tu, Li, and coworkers [58] described the first domino [4-1-1]/ [3- -2- -l]/[5- -l] and double [4-1-3] cyclization reactions of o-phthalaldehyde 94 and 4-hydroxy-6-methyl-2H-pyran-2-one 95 with N-substituted enaminones 57 (Scheme 12.37). Using N-substituted 3-aminocyclohex-2-enones as enaminone led to pentacyclic pyrano[3, 2 2,3]indeno[2,l-c]pyridines 96 in 44-68% yield, whereas by employing N-substituted 4-aminofuran-2(5H)-ones the reaction occurred in another direction to form multifunctionalized pentacyclic pyrano[4,3- j]oxepines 97. This work provides an attractive strategy for the construction of structurally diverse pentacyclic oxa-azaspiro and oxa-azabridged skeletons. 

Cignarella, G., Loriga, M., Pinna, G. A., Pirisi, M. A., Schiatti, P. and Selva, D. 1982. Unexpected anti-inflammatory activity of rigid structures derived from antihypertensive 6-arylpyridazinones. III. Synthesis and activity of 7-fluoro- and 5-keto-5H-indeno[l,2-c]pyridozines. Farmaco-Ed. Sci. 37 133-144. 

Other Names Benz[b]indeno[l,2-d]pyran-3,4,6a,9,10(6H)-pentol, 7,llb-dihydro Benz[b]indeno [l,2-d]pyran-3,4,6a,9,10(6H)-pentol, 7,llb-dihydro, (6aS-cis)- (+)-Hematoxylin Haematoxylin Hematoxylin Hematoxyline Hydroxybrasilin Hydroxybrazilin NSC 270085 CA Index Name Benz[b]indeno[l,2-d]pyran-3,4,6a,9,10(6H)-pentol, 7,llb-dihydro, (6aS,llbR)-CAS Registry Number 517-28-2 Merck Index Number 4637 Chemical Structure... 

Fig. 5 Fully conjugated indeno[l,2-h]fluorene 2 and resonance structures of 22...

The first account of the indeno[2,l-a]fluorene core in the literature dates to 1939 when Weizmann investigated polycyclic structures and their potential carcinogenic properties [23]. Intramolecular Friedel-Crafts acylation of 3,6-diphenylphthalic anhydride (113) in refluxing CS2 afforded fluorenone carboxylic acid 114 (Scheme 33). Acid chloride formation and subsequent cyclization in concentrated sulfuric acid generated the parent indeno[2,l-a]fluorene dione 115 in 5% yield with respect to 113. This was reaffirmed by Deuschel in 1951 where 115 is obtained in 72% under the same conditions [26]. 

Like 2, the indeno[2,l-a]fluorene isomer also supports full conjugation, illustrated by 3, where an o-xylylene core (o-quinodimethane) is present in the structure (Fig. 14). As such, interest in this structure lies in the potential of the o-xylylene core to exist as a stable open shell configuration (3b). 

Although the PAHs are similar, they have structural differences that are the basis for differences in metabolism and relative carcinogenicity. The metabolism of the more carcinogenic, alternant (equally distributed electron density) PAHs, such as benzo(a)pyrene, benzo(a)anthracene, and dibenz(a,h)anthracene, seems to differ in some ways from that of nonalternant (imeven electron density distribution) PAHs, such as fluoranthene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(j)fluoranthene, and indeno(l,2,3-cd)pyrene [31]. As can be seen, most of the studies on the metabolic pathways of PAHs have been done on rodent, therefore little is known on the metabolism of these compounds in nonrodent species. Due to specie differences there may be some slight differences in the enzymes that activate PAHs and in the formation of DNA adducts. 

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