Derivatives, table

The presence of thiophene and its derivatives in crude oils was detected in 1899, but until 1953, the date at which the methyl-thiophenes were identified in kerosene from Agha Jari, Iran crude oil, it was believed that they came from the degradation of sulfides during refining operations. Finally, their presence was no longer doubted after the identification of benzothiophenes and their derivatives (Table 8.9), and lately of naphthenobenzothiophenes in heavy cuts. 

The first quantitative studies of the nitration of quinoline, isoquinoline, and cinnoline were made by Dewar and Maitlis, who measured isomer proportions and also, by competition, the relative rates of nitration of quinoline and isoquinoline (1 24-5). Subsequently, extensive kinetic studies were reported for all three of these heterocycles and their methyl quaternary derivatives (table 10.3). The usual criteria established that over the range 77-99 % sulphuric acid at 25 °C quinoline reacts as its cation (i), and the same is true for isoquinoline in 71-84% sulphuric acid at 25 °C and 67-73 % sulphuric acid at 80 °C ( 8.2 tables 8.1, 8.3). Cinnoline reacts as the 2-cinnolinium cation (nia) in 76-83% sulphuric acid at 80 °C (see table 8.1). All of these cations are strongly deactivated. Approximate partial rate factors of /j = 9-ox io and /g = i-o X io have been estimated for isoquinolinium. The unproto-nated nitrogen atom of the 2-cinnolinium (ina) and 2-methylcinno-linium (iiiA) cations causes them to react 287 and 200 more slowly than the related 2-isoquinolinium (iia) and 2-methylisoquinolinium (iii)... 

Lithiated indoles can be alkylated with primary or allylic halides and they react with aldehydes and ketones by addition to give hydroxyalkyl derivatives. Table 10.1 gives some examples of such reactions. Entry 13 is an example of a reaction with ethylene oxide which introduces a 2-(2-hydroxyethyl) substituent. Entries 14 and 15 illustrate cases of addition to aromatic ketones in which dehydration occurs during the course of the reaction. It is likely that this process occurs through intramolecular transfer of the phenylsulfonyl group. 

Quantum chemistry methods allow the prediction of the ultraviolet transitions in good agreement with the experimental values in the case of thiazole and its three methyl derivatives (Table 1-18). A very weak absorption has been indicated at 269.5 nm that could correspond to an n- TT transition given by calculation at 281.5 nm (133). Ultraviolet absorption spectroscopy has been investigated in connection with steric interactions in the A-4-thiazoline-2-thione (74) series (181). It was earlier demonstrated by NMR technique that 4-alkyl-3 isopropyl-A-4-thiazoline-2-thiones exist in solution as equilibrium mixtures of two conformers (75 and 76), the relative populations of which vary with the size of R4 (182) for R4 = rBu the population of rotamer A is 100%, whereas for R4 = Me it is only 28%. Starting from the observed absorption wavelength for... 

A. Chloroacetaldehyde and Derivatives (Thiazole and its 2-Monosubstituted Derivatives) (Table II-l)... 

Alkyl. Aryl. Aralkyl, and Related Thiazole Derivatives TABLE riI-90. 4-ARALKYLTHlAZOLES... 

Higher aliphatic alcohols (C —C g) are produced ia a number of important industrial processes using petroleum-based raw materials. These processes are summarized in Table 1, as are the principal synthetic products and most important feedstocks (qv). Worldwide capacity for all higher alcohols was approximately 5.3 million metric tons per annum in early 1990, 90% of which was petroleum-derived. Table 2 Hsts the major higher aliphatic alcohol producers in the world in early 1990. 

Brackets signify a trivial name no longer ia use. At 101.3 kPa = 1 atm unless otherwise noted ia kPa as a subscript. At 20°C unless otherwise noted by a superscript number (°C). At 20°C unless otherwise noted. To convert to cal, divide by 4.184. 70°C. Heat of combustion (Uquid). At50°C. To convert kPa to mm Hg, multiply by 7.5. In the alkenoic series of molecular formula 2 2 metbacrylic, undecjlenic, oleic, and emcic acids have important appHcations (Table 2). Acryhc and metbacrylic acids have a petrochemical origin, and undecylenic, oleic, and emcic acids have natural origins (see Acrylic ACID AND DERIVATIVES Methacrylic acid and derivatives). Table 2. Physical Properties of the Straight-Chain Alkenoic Acids, (2n-2) 2 ... 

Chemical shifts for aromatic azoles are recorded in Tables 14-17. As for the proton spectra, fast tautomerism renders two of the chemical shifts equivalent for the NH derivatives (Table 14). However, data for the AT-methyl derivatives (Table 15) clearly indicate that the... 

The salts of the thiol react with alkyl and acyl halides to form alkyl or acyl derivatives (Table II). For a discussion of the constitution of these compounds see Section IV, D. 

However, the use of a HPLC separation step enabled a remarkable acceleration of the deconvolution process. Instead of preparing all of the sublibraries, the c(Arg-Lys-O-Pro-O-P-Ala) library was fractionated on a semipreparative HPLC column and three fractions as shown in Fig. 3-2 were collected and subjected to amino acid analysis. According to the analysis, the least hydrophobic fraction, which eluted first, did not contain peptides that included valine, methionine, isoleucine, leucine, tyrosine, and phenylalanine residues and also did not exhibit any separation ability for the tested racemic amino acid derivatives (Table 3-1). 

Benzene-1,2-diamine or derivatives are generally employed as the diamino component in ring-closure reactions with 1,2-dicarboxylic acids or derivatives (Table 2). 

Simple heating of various other anthranilic acid derivatives often leads to the 1,5-diazocine derivatives (Table 3).3 "12... 

In addition to the problems of substrate- or reagent-controlled stereoselectivity, the problem of simple synjanti diastereoselectivity arises. Most studies have been performed on the crotyl derivatives. Table 2 summarizes some of these under the latter aspect. Essentially all types of reagents related to the appropriate 2-propenylmetal reagents collected in Table 1 are known. 

Several bacterial enzymes can modify antibiotics to inactive derivatives (Table 2). 

Once equation (10.158) has been obtained for relating Cy. m to T for a Debye solid, equations relating (Um - U0 m), (Hm - Uo.m), and Sm to T can be derived. Tables of values, expressed in terms of 9d/T. can be found in Table A4.7, Appendix 4, with more extensive tables found in the literature1 to calculate these thermodynamic properties. 

A number of carboxylic acids are found in nature and also present in metabolic pathways. Accordingly, if monobasic acids are smoothly decarboxylated, they are expected to provide us with new routes to supply useful materials for chemical industry without depending on petroleum. Actually, there are some already known examples. The representative examples are the decarboxylation of cinnamic acid derivatives (Table 8). ... 

The case of butane is noteworthy since the selectivity at low conversions indicates that there is no selectivity in the overall hydrogenolysis step between n- and sec-butyl zirconium surface intermediates, while earUer studies had shown that the -alkyl zirconium complexes were more stable than sec-alkyl derivatives (Table 3 and Scheme 23) [94]. 

From the inhibitory data of Suzuki et al. [52] for a series of isoaurostatin derivatives (VIII) against topo II, Eq. 17 was derived (Table 13) ... 

A series of 5H-indolo[2,3-b]quinoline derivatives (XVII) was synthesized by Kaczmarek et al. [70] as novel DNA topo II inhibitors. Using their data for topo Il-induced DNA cleavage by this compound series (XVII), Eq. 18 was derived (Table 14) ... 

Eissenstat et al. [71] synthesized a series of quinolone derivatives (XVIII) and evaluated their inhibitory activities against topo II. From their data Eq. 19 was derived (Table 15) ... 

Optical sensors for oxygen are among the few sensors, which have found practical application for process-monitoring and clinical diagnostics. They are generally based on compounds such as platinum porphyrins or ruthenium phenanthroline derivatives (Table 17) which show a decrease in luminescence upon exposure to molecular oxygen15. 

Crotonic esters and certain homologues, when converted to their enolates with LDA and treated with stannyl and germyl chlorides, afford the y-metallo derivatives (Table 10)57. In contrast, silylation of these enolates leads to the 0-silyl derivatives. Interestingly, the halostannane derivatives show a strong preference for the (Z) geometry suggestive of a donor-acceptor interaction between the carbonyl oxygen and the electropositive tin atom,... 

The favorable bismuth-sulfur bond translates into thermal and hydrolytic stability for the thiolates of bismuth, which are currently more numerous than the alkoxide derivatives (Table II). Various monomeric trithiolates have been identified, and most adopt predictable structural formulas, although the solid-state structures reveal interesting intermolecular and intramolecular interactions. 

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