Privileged structural motifs

Rational Selection of Building Blocks Based on Privileged Structural Motifs... 

Analysis of Privileged Structural Motifs Structure Dissection Rules... 

To correctly address the problem of identification of target-specific privileged motifs, one should take into account the phenomenon of bioisosterism [26]. Thus, several different bioisosteric structures can constitute only one distinct privileged structural motif. In order to include all possible bioisosteric analogs into one cluster, we use a special algorithm of ChemoSoft based on a collection of rules for bioisosteric conversions described in literature. AH bioisosteric analogs are considered similar with similarity coefficient 1 if they have identical substituents around the central bioisosterically transformed fragment. 

I 72 CPCR-specific Combinational Libraries Based on the Concept of Privileged Substructures Tab. 12.4 Some privileged structural motifs of Dopamine D2 agonists... 

As reviewed in this chapter, cinchona alkaloids have played a crucial role in the development of asymmetric phase-transfer catalysis since its advent, and today constitute a privileged structural motif that may be widely utilized for the design of new chiral quaternary ammonium salts. These benefits are due not only to the... 

Our screening collections therefore have a biogenic bias because we have selected them from ideas based on knowledge of biochemistry. We therefore rediscover binding events through screening, and we ascribe this rediscovery to privileged structure motifs ... 

Oxindoles with an all-carbon quaternary center at the C3 position are privileged structural motifs found in many pharmaceuticals and alkaloid natural products [90]. The asymmetric Michael addition of oxindoles proved to be an efficient method for the construction of these structural motifs and a wide range of electrophiles such as a,(3-unsaturated aldehydes [91], ketones [92], sulfones, nitroalkenes [93], and 2-chloroacrylonitrile [94] have been weU studied in recent years (Scheme 5.45). 

Spirocycles have received considerable interest in the last decade as a privileged structural motif. The conformational restriction associated with the structural rigidity and the chirality of their quaternary center influences considerably their biological activities (antimicrobial, antitumor, antibiotic)... 

Heterocyclic skeleton is a "privileged" structural motif in innumerable natural products and synthetic compoxmds often exhibiting relevant biological properties [1]. More specifically, nitrogen heterocycles are abundant in nature existing as part of vitamins, hormones, antibiotics, and alkaloids. 

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