24285-39-0Relevant articles and documents
O-methyl-isourea carboxylic acid methyl ester preparation
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Paragraph 0034-0035, (2017/01/26)
The invention discloses a method for preparing O-methyl isourea methyl formate. According to the method, O-methyl isourea bisulfate and methyl chloroformate are put in the mixed solvent of chloroform-water or toluene-water and the like, and O-methyl isourea methyl formate is prepared under alkaline conditions. The method has no step of synthesizing O-methyl isourea sulfate, the production period is shortened, the energy consumption is reduced, the labor intensity of workers is reduced, and the production capacity is improved; the product cost is reduced and the environmental pollution is reduced due to no use of methanol and sodium hydroxide in the method; the water amount in the mixed solvent is strictly controlled, large water amount results in low yield due to large solubility of the product in water; small water amount results in difficult separation of the product due to poor dissolution of inorganic salts produced by the reaction; and the yield is improved by 1-2 percent.
Process for the preparation of 9-deazaguanine derivatives
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Page 19, (2010/02/09)
Derivatives of 9-deazaguanine are prepared by reacting an aldehyde or ketone with a dialkylaminomalonate to form the corresponding enamine. The enamine is then reacted with a base to form a cyclic pyrrole. The cyclic pyrrole is reacted with an urea compound or a derivative of carbamimidoic acid to provide a protected guanidino compound. The guanidino is converted to the desired 9-deazaguanine derivative by reacting with trifluoracetic acid or with an alkoxide or hydroxide followed by neutralization with an acid.