Structural variants

A methodical, logical and scientific approach to the various ways and means to justifiably and usefully exploit and recognize the structural variants originally deduced from general organic reaction modes may be categorized under two heads, for instance  

Consequently, these two distinct categories of reaction types may be summarized in the shape of tabular forms depicting the range of structures arrived at by specific nucleophile— electrophile combinations as given in Table-1 below. Thoughtfully, each side of the Table-1 may be regarded as a half-reaction belonging to either oxidation-reduction or acid-base chemistry. 

However, in the same vein the various range of electrophilic reactions of unsaturated carbon-carbon bonds may also be summarized and illustrated as in Table-2. If one duly makes use of the contents of Table-1 and 2, loaded with a copious valuable and condensed informations, one should be benefited in two major aspects, namely  

Salient Features. Various salient features from Table-1 and 2 are  

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Most reports concern Azafenidin, 134 (97MI3). There are numerous structural variants, mainly involving different 2-aryl substituents, such as 300... 

New structural variants of crosslinked permeable polyelectrolytes, copolymers of AA or MA, and bi-or trivinyl comonomers with vinyl groups relatively distant from each other were obtained by predpitative copolymerization [16-21]. 

Zn, Al, Ga, In, Ge, Sn, Sb Structure variants with an extended statistical distribution or with partial ordering... 

This next example involves the well-known plant kawa. A psychoactive beverage made from the roots of this plant is used widely in the islands of the southwestern Pacific Ocean either for ritualistic or routine consumption. Kava is the common name for Piper methysticum Forst. f. from which several compounds responsible for the pharmacological activity have been isolated and identified. Representative structures of the family of styrylpyrones, commonly called kavalactones, are given in Fig. 6.6. The compounds are based upon a carbon skeleton consisting of a styryl function (C C ) attached to a six-membered lactone ring. The fundamental compound, kawain, is shown as structure [547]. Structural variants include... 

Structural variants in structure 11 appear compatible with high-affin-ity binding to antithrombin. Thus, the acetoxyl group of residue ANA6S could be removed (by hydrazinolysis) and replaced by a sulfate group without loss of affinity.172 Natural, high-affinity oligosaccharides con-... 

Two new amino carboxylate BFCA macrocycles were synthesized, labeled with U1ln and 153Sm, and in vitro stabilities were assessed. These ligands were structural variants of DOTA with one carboxymethylene arm replaced by an ethyl amine.165... 

In case of allocation conflicts one has to choose a different time, a different structural variant (production version) or even both. The process of creating feasible production plans is denoted as scheduling. To support the solution of scheduling problems, a scheduling system is used. 

The most potent of the known hallucinogenic agents is LSD. It is orally active in man at doses of about 0.1 mg (0.05 to 0.25 mg). The vast majority of human studies involving LSD and its structural variants were performed in the 1950s and 1960s and have been reviewed in great detail (24,154,196,208). Therefore, some of the key structure-activity relationships are briefly highlighted here only for the sake of completeness. 

The purpose of the business model is to represent all the vocabulary that is used by the people in the business. It can augment or form a more structured variant of the company or project glossary. Its advantage over the plain glossary or dictionary of terms is that it can summarize complex relationships readily. 

According to Parthe et al. (1993), a standardization procedure is necessary in the presentation of the relevant data characteristic of a crystal structure (see also Parthe and Gelato 1984). A convenient description of the structure types is then possible using the Wyckoff sequence (the letters of the occupied Wyckoff sites). This allows a finer classification of structure types and offers suggestions not only for recognizing isotypic structures but also possible structural relationships like substitution, formation of vacancy or filled-in structure variants. 

Notice that not in all the compilations and not by all the researchers are such structural variants considered as separate structure types. It seems however useful to speak of, say, the cI58-Ti5Re24 type structure when the elements are orderly distributed in selected sites of the Mn type, whereas it could really be more appropriate to speak of the cI58 a -Mn type even in the case of a binary combination (a solid solution) in which all the sites of this structure are occupied, at random in the same proportion, by the different components. 

Atoms in the different positions of various tI26-ThMn12 structure variants ... 

Faure, S., Meyer, L., Costagliola, D., et al. (2000) Rapid progression to AIDS in HIV-l- individuals with a structural variant of the chemokine receptor CX3CR1. Science. 287, 2274-2277. 

The base-catalyzed cleavage of B-hydroxynitrosamines occurs as is shown in equation 4 to produce a smaller fragment nitrosamine and the carbonyl compound. This reaction is formally analogous to the retroaldol cleavage of a B-hydroxyaldehyde or ketone and as we will see below, appears to be mechanistically related to this transformation. We have demonstrated that this reaction occurs with a wide range of structurally variant B-hydroxynitrosamines 5). Table 1 lists the structure, yield, and reactivity estimate of the compounds that we have studied so far under the same conditions. A variety of conditions have been used to in-... 

Fluorescence spectroscopy is reported for a benzo[4,5]thieno[2,3- / thiazolium iodide salt <2004SAA129>. A wide variety of structural variants of the nonconjugated heterocycles have reported X-ray crystallographic data however, perhaps surprisingly, only very limited X-ray structural information has been reported for the fully conjugated heterocycles. 

A structural variant of a nucleotide is a nucleoside, which is a nucleotide with the phosphate group removed. 

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