Functional group diversity

Branchaud BP, CT Walsh (1985) Functional group diversity in enzymatic oxygenation reactions catalyzed by bacterial flavin-containing cyclohexanone oxygenase. J Amer Chem Soc 107 2153-2161. 

Structural type. Diversity-oriented synthesis is a new strategy for constructing libraries with both skeletal and functional group diversity. 

Martin and co-workers counted the total number of substructural fragments up to seven bonds long found in entire libraries as an estimate of chemical functional group diversity. They showed that although synthetic oligomeric combinatorial peptoid libraries were far more diverse than combinatorial biopolymer libraries, they still contained only about as many substructures as just the 45 top selling small molecule drugs. 

Functional group diversity - variation in the functional groups present... 

In 2013, Sengmany eta/. [184] reported the Ni-catdyzed synthesis of 3-amino-6-aryl- and 3-amino-6-heteroarylpyridazines - compounds that exhibit diverse biologic2il activities - using an electrochemical method. A large functional group diversity was shown on both the 3-amino-6-chloropyridazine and the aryl or heteroaryl halide reagent. The yields were satisfactory. 

In this paper we report our recent results in this area. The following points are discussed (i) the hydrogen-bonding motif and molecular modules, (ii) the assembly process, (Hi) the development of suitable characterization methods for self-assembled systems, (iv) the generation of functional group diversity, and (v) the progress towards the creation of a cavity within the assembly. 

In the hydrogen-bonded assemblies (X)3 (DEB)6 six fiinctionalizable sites R are gathered around the box-like cavity. In view of our objective to generate functional group diversity in or around non-covalently assembled cavities, we studied how the nature of the functionality at position R affects the stability of such calix[4]arene box-like assemblies in solution [13]. 

I he diverse range of phannacological actions of this structural class documents the belief that the naphthalene nucleus consists of a scaffold upon which vanous functional groups can be arranged tnd that the action elicited is a consequence of receptor response to the kind and spatial arrange ment of these functions... 

Much work is still appearing on the [l,2,4]triazino[5,6-b]indole ring system since its first synthesis, due to its varied biological properties. Moreover, it has been used as a carrier for diverse functional groups suitable for the development of several chemotherapeutic agents. In addi-... 

Evolution has provided the cell with a repertoire of 20 amino acids to build proteins. The diversity of amino acid side chain properties is enormous, yet many additional functional groups have been selectively chosen to be covalently attached to side chains and this further increases the unique properties of proteins. Diese additional groups play a regulatory role allowing the cell to respond to changing cellular conditions and events. Known covalent modifications of proteins now include phosphorylation, methylation, acetylation, ubi-quitylation, hydroxylation, uridylylation and glycosyl-ation, among many others. Intense study in this field has shown the addition of a phosphate moiety to a protein... 

The reaction of tert-alkyl Grignard reagents with carboxylic acid chlorides in the presence of a copper catalyst provides ieri-alkyl ketones in substantially lower yields than those reported here.4,14 The simplicity and mildness of experimental conditions and isolation procedure, the diversity of substrate structural type, and the functional group selectivity of these mixed organocuprate reagents render them very useful for conversion of carboxylic acid chlorides to the corresponding secondary and tertiary alkyl ketones.15... 

Enzyme-mediated oxidation reactions offer highly diverse options for the modification of existing functional groups as well as for the introduction of novel function in chiral catalysis. Biooxidations often enable us to obtain complementary solutions to metal-assisted transformations and organocatalysis and are considered one of the important strategies of green chemistry . 

Another interesting biooxygenation reaction with alkenes, recently identified, represents an enzymatic equivalent to an ozonolysis. While only studied on nonchiral molecules, so far, this cleavage of an alkene into two aldehydes under scores the diversity of functional group interconversions possible by enzymatic processes [121,122]. 

Proteins derive their powerful and diverse capacity for molecular recognition and catalysis from their ability to fold into defined secondary and tertiary structures and display specific functional groups at precise locations in space. Functional protein domains are typically 50-200 residues in length and utilize a specific sequence of side chains to encode folded structures that have a compact hydrophobic core and a hydrophilic surface. Mimicry of protein structure and function by non-natural ohgomers such as peptoids wiU not only require the synthesis of >50mers with a variety of side chains, but wiU also require these non-natural sequences to adopt, in water, tertiary structures that are rich in secondary structure. 

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