24285-39-0Relevant academic research and scientific papers
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.
Preparation method of O-methyl isourea sulphate
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Paragraph 0012, (2016/12/01)
The invention discloses a preparation method of O-methyl isourea sulphate. Reaction is divided into two process, a first process comprises the steps of adding urea and dimethyl sulphate into a reactor, mixing, then adding water and sulphuric acid, and carrying out reaction in the first process; and a second process comprises the steps of directly adding calcium hydroxide solid into a reaction liquid obtained in the first process in the reactor for carrying out reaction in the second process, and adding methyl alcohol after the reaction in the second process is completed for carrying out recrystallization, and filtering, so that the product O-methyl isourea sulphate is obtained. The total yield of the reactions in the two processes is more than 80%, and mass content of the product O-methyl isourea sulphate is more than 98%. The preparation method of the O-methyl isourea sulphate has the advantages that the reaction process is a 'quasi-one pot method' reaction, technology is simple, raw materials are available, solvent usage amount is small, operation is easy and yield is high; meanwhile, calcium hydroxide is adopted as the catalyst, fewer three wastes are produced in a preparation process, and environmental protection is facilitated; and a byproduct calcium sulphate can be applied to cement production, and comprehensive cost is further reduced, thereby being applicable to industrialized production.
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.
Selective binding and analysis of macromolecules
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Page 19-20, (2008/06/13)
There is disclosed a method for selectively binding micromolecules having a lysine functionality comprising the steps of: providing a sample containing one or more species of macromolecules, each having a lysine functionality; providing a binding reagent having the formula X-NH-C(=NH)-OR or X-L-NH-C(=NH)-OR where X is an affinity label that selectively binds to a capture reagent, R is a residue group, and L is a linker moiety; introducing the binding reagent to the sample so as to effect a guanidination reaction between the binding reagent and said one or more species of macromolecules, thereby producing one or more affinity label containing homoarginine derivatives; optionally modifying the affinity label containing homoarginine derivatives to produce further affinity label containing homoarginine derivatives; and capturing affinity label containing homoarginine derivatives using the capture reagent that selectively binds X.
