Structures Generic

More than 24 phenothiazine and the reiated thioxanthene derivatives are used in medicine, most of them for psychiatric conditions. The structures, generic and trade names, dose, and side effects of phenothiazines and thioxanthenes currentiy used as neuroieptics are iisted in Tabie 22.1. 

Niunerous retinoids are now known and these cannot be represented by a single generic structure. Generic stucture types I, II, and III, however, represent the structure of most retinoids synthesized to date Figure LI). Compounds represented by structure type I include isomers and closely related analogues of retinoic acid (1), acitretin (2) and its ethyl ester (etretinate), and mono-aromatic heteroarotinoids such as (6), (15)-(17), and (54)-(57). Retinoids type II include substituted naphthalene, stilbene, azobenzene, and diaromatic amides, and other hetero-substituted analogues... 

Dyes are classified and discussed by structure. To aid in this identification the AATCC and The Society of Dyers and Colorists have published the Color Index. This publication details dye classifications by structure, generic name and an identifying Constitution Number. Other information listed is solubility parameters, heat and light stability and chemical resistance. Recently, the larger dye manufacturers have chosen not to disclose a great deal of information concerning new dyes. 

Chemical structure Generic term [trivial name] Svennerholm Svennerholm modified Wiegandt Wiegandt modifiecK Korey et al."... 

ROSDAL is used in the Beilstein-DIALOG system [17] as a data exchange format. The code can represent not only full structures and substructures but also some generic structures. 

Maikush structures are mainly used in patents, for protecting compounds related to an invention. The first generic claim, submitted by Markush, was granted in 1924 by the US Patent Office [87-90]. 

In contrast to canonical linear notations and connection tables (see Sections 2.3 and 2.4), fragment codes arc ambiguous. Several different structures could all possess an identical fragment code, because the code docs not describe how the fragments arc interconnected. Moreover, it is not always evident to the user whether all possible fi aginents of the stmetures ai e at all accessible. Thus, the fragments more or less characterise a class of molecules this is also important in generic structures that arise in chemical patents (sec Section 2.7.1)... 

In order to allow any multiple chlorination of the biphenyl skeleton, the user may define an atom list (eonsisting of hydrogen and chlorine atoms) and substitute all H-atoms by this list. One may click on the drop-down selection box behind the element icons, select the options Generics. .set the user-defined atom to A1 and quit by the OK button. As a result this atom selection is active for the subsequent drawing steps. After this atom list is drawn ten times as the ten substituents, its composition has to be defined by clicking the A, icon on the left-hand side of the structure editor and by selecting H and Cl in the periodic table (Figure 5-16). 

An alternative to retrieval by means of an atom list is a structure search performed by means of a user-defined generic group which contains only chlorine... 

It Is cmphasi < cd that both versions of the generic structure query may include the parent compound and monochlorinated derivatives. 

Part of the structure editor screen with dialog windows to specify the attachment 1 user-defined generic groups. 

Patent databases are therefore integrated databases because facts, text, tables, graphics, and structures are combined. In patents that include chemical aspects (mostly synthesis or processing), the chemical compounds are often represented by Markush structures (see Chapter 2, Section 2.7.1). These generic structures cover many compound families in a very compact maimer. A Markush structure has a core structure diagram with specific atoms and with variable parts (R-groups), which are defined in a text caption. The retrieval of chemical compounds from Markush structures is a complicated task that is not yet solved completely satisfactorily. 

The controversy seemed then to be closed. In 1890 Hantzsch had already started his work on the structure of oximes, and his synthetic work on heterocycles was practically ended. However, 27 years later, in July 1919, Tcherniac published a new paper entitled TTiiocyanoacetone and its derivatives as isomerides (33), where, after the description of improved and generalized methods for the preparation of thiocyanoacetone he came to the explosive conclusion that the substance which has been known since 1887 as hydroxymethylthiazole is not a thiazole at all. It might be called 2-imino-4-methylthioxole, but for the sake of simplicity, and in view of the now proved existence of two other isomerides of thiocyanoacetone, it seems preferable to adopt the generic... 

Fig. 1. Model of a ligand gated ion channel (LGIC) where (a) is the structure of a generic LGIC subunit showing the two cysteine (Cys) residues common to all LGIC subunits, and (b) shows the arrangement of five such subunits as a pentamer having psuedo-cyclic symmetry delineating a gated, fluid-filled...

Table 3 lists the structures and generic names of the principal penicillins in current medical usage, and Table 4 indicates in summary form the relative antibacterial properties of these compounds. The reader is urged to consult reviews such as (B-77MI51106) for a more complete treatment, since summaries such as Table 4 inevitably omit a large amount of important detail. 

This section briefly reviews prediction of the native structure of a protein from its sequence of amino acid residues alone. These methods can be contrasted to the threading methods for fold assignment [Section II.A] [39-47,147], which detect remote relationships between sequences and folds of known structure, and to comparative modeling methods discussed in this review, which build a complete all-atom 3D model based on a related known structure. The methods for ab initio prediction include those that focus on the broad physical principles of the folding process [148-152] and the methods that focus on predicting the actual native structures of specific proteins [44,153,154,240]. The former frequently rely on extremely simplified generic models of proteins, generally do not aim to predict native structures of specific proteins, and are not reviewed here. 

It is beyond the scope of this chapter to review structure and bonding in each class of engineering carbons listed in Table 5. Instead, a generic description of microstructure and bonding in these materials will be attempted. The evolution in understanding of the structure of engineering carbons and graphites has followed the initial application of X-ray diffraction and subsequent application... 

A fresh start has been made by Samuel Allen and Edwin Thomas of MIT, with The Structure of Materials (1998), the first of a new MIT series on materials. The authors say that our text looks at one aspect of our field, the structure of materials, and attempts to define and present it in a generic, materials catholic way. They have succeeded, better than others, in integrating some crucial ideas concerning polymers into mainline materials science. 

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