The identification and characterization of hydrazinyl urea-based antibacterial agents through combinatorial chemistry

L J Wilson1, T W Morris, Q Wu

  • 1Procter & Gamble Pharmaceuticals, Healthcare Research Center, Mason, OH 45040, USA. lwilson3@prius.jnj.com

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Preparation of 1° Amines: Azide Synthesis

Direct alkylation of ammonia produces polyalkylated amines, along with a quaternary ammonium salt. To exclusively prepare primary amines, the azide synthesis method can be used.
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
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Diazonium Group Substitution: –OH and –H

Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
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Aryldiazonium Salts to Azo Dyes: Diazo Coupling

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Preparation of 1° Amines: Gabriel Synthesis01:28

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Methods of Classification and Identification

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