1. Preparation of ETO Starting from butene-2-aldehyde, under the catalysis of tertiary amines, it is added with ethanethiol to form 3-ethylthiobutyraldehyde; hydrolysis of methyl acetoacetate to sodium acetoacetate; then 3 Ethylthiobutyraldehyde reacts with sodium acetoacetate and reacts with N-methylhexylamine as a catalyst at 20-40°C to form 6-ethylthio-3-hepten-2-one (ETO for short).
2. Preparation of CDNA Michael addition to dimethyl malonate in the presence of sodium methoxide followed by cyclization, hydrolysis, and decarboxylation yields 5-[2-(ethylthio)propanol. Based on 1,3-cyclohexanedione (abbreviated as CDNA).
3. Diazodipin Synthetic DNA acylation is performed with butyryl chloride as an acylating agent. Since butyryl chloride is easily hydrolyzed, the reaction should be carried out in an organic solvent. A phase transfer catalyst is used. The acylation product is 4-N,N-. The dimethyldipyridine catalyzes the translocation rearrangement. The rearranged product is then condensed with ethoxylamine under mild conditions at 40-60° C. to synthesize hydrazine, and sulfamidin is obtained at a relatively high yield.