Amides biologically significant reactions

All synthesis of amide bonds of biological significance are dependent upon energy, commonly in the form of ATP and of magnesium or manganese ions as cofactor. Some syntheses of amide bonds take place without the presence of any known coenzyme and others are dependent upon coenzyme A (CoA). The synthesis of acetyl sulfanilamide from acetate and sulfanilamide is an amide bond synthesis dependent upon CoA. This conjugation reaction has been studied by Chou and lipmann (1952) who showed that two enzymes took part in the reaction and that acetyl-l.S CoA was an intermediate product. 

Thus, Af-acyloxyl-A-alkoxyl substitution in these anomeric amides significantly impacts upon their biological activity in two ways Inversely by affecting the ease of their nucleophilic reactivity towards intracellular bionucleophiles and hence their intracellular survival, and directly by controlling their ability to undergo Si 2 reactions once ultimately bound in the major groove of DNA. 

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