Functional group Fusion

Substitution. Substitution products retain the same nuclear configuration as naphthalene. They are formed by the substitution of one or more hydrogen atoms with other functional groups. Substituted naphthalenes of commercial importance have been obtained by sulfonation, sulfonation and alkah fusion, alkylation, nitration and reduction, and chlorination. 

Functional groups, 330,335 Fundamental property, 78 unit of electricity, 241 Furnace, electric arc, 404 Fusion, heat of, 68 pure substances, table, 69 Fusion, nuclear, 121, 419... 

Fusion of a barbituric acid motif and a pyrone ring afforded compounds containing a novel pyranopyrimidine core (L) that were discovered as GPR109A agonists [92,93]. This core appears to be distinct from other fused bicyclic cores such as xanthine and anthranilide based on their poor overlap. Furthermore, several compounds, exemplified by 39 and 40, provided remarkable potency in the cAMP assay. The critical acidic functional group is present as the N-PI of barbituric acid motif which has a calculated pKa of 8 [82]. 

This section is concerned with reactions that result in the fusion of one or more additional rings to the indolizine system. Of course, an indoli-zine synthesis can be designed in which the functional groups are oriented for cyclization. An example is the formation of the indolizino-[l,2-c]quinoline 132 (Scheme 17).199... 

Lateral chain modifications on QDO and PDO have been well documented in the literature. The described reactions have shown modifications in specific functional group—i.e., acylations, alkylations, decarboxylations, hydrolysis, rearrangements, substitutions—or the production of a new heterocycle, fusioned or not. Examples of the most recent descriptions are depicted in Fig. 6 [64-66],... 

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