72702-57-9Relevant articles and documents
Tulobuterol crystal form and preparation method thereof
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, (2021/04/28)
The invention provides a tulobuterol crystal form and a preparation method thereof. The preparation method comprises the following steps of: dissolving tulobuterol in ethyl acetate and other good solvents, dropwisely adding n-heptane and other poor solvents into the system, filtering, taking the filter cake, and drying the filter cake to obtain the tulobuterol crystal form crystal. The crystal form is high in purity and good in stability, has superiority in process production, and is suitable for long-term storage in the preparation process.
Lipase mediated enzymatic kinetic resolution of phenylethyl halohydrins acetates: A case of study and rationalization
Fonseca, Thiago de Sousa,Vega, Kimberly Benedetti,da Silva, Marcos Reinaldo,de Oliveira, Maria da Concei??o Ferreira,de Lemos, Telma Leda Gomes,Contente, Martina Letizia,Molinari, Francesco,Cespugli, Marco,Fortuna, Sara,Gardossi, Lucia,de Mattos, Marcos Carlos
, (2020/02/18)
Racemic phenylethyl halohydrins acetates containing several groups attached to the aromatic ring were resolved via hydrolysis reaction in the presence of lipase B from Candida antarctica (Novozym 435). In all cases, the kinetic resolution was highly selective (E > 200) leading to the corresponding (S)-β-halohydrin with ee > 99 %. However, the time required for an ideal 50 % conversion ranged from 15 min for 2,4-dichlorophenyl chlorohydrin acetate to 216 h for 2-chlorophenyl bromohydrin acetate. Six chlorohydrins and five bromohydrins were evaluated, the latter being less reactive. For the β-brominated substrates, steric hindrance on the aromatic ring played a crucial role, which was not observed for the β-chlorinated derivatives. To shed light on the different reaction rates, docking studies were carried out with all the substrates using MD simulations. The computational data obtained for the β-brominated substrates, based on the parameters analysed such as NAC (near attack conformation), distance between Ser-O and carbonyl-C and oxyanion site stabilization were in agreement with the experimental results. On the other hand, the data obtained for β-chlorinated substrates suggested that physical aspects such as high hydrophobicity or induced change in the conformation of the enzymatic active site are more relevant aspects when compared to steric hindrance effects.
Method for synthesizing tulobuterol
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Paragraph 0015; 0031-0032; 0045-0048, (2020/01/03)
The invention discloses a method for synthesizing tulobuterol. According to the method, 1-(2-chlorophenyl)-2-bromoethanone (compound 3) and 1-(2-chlorophenyl)-2,2-dibromoethanone (compound 10) can besimultaneously utilized to synthesize the tulobuterol. In an original route, the compound 10 is a by-product of synthesis of the compound 3, and about 10-15% of the compound 10 is not fully utilized.The method provided by the invention can improve the synthesis yield of the tulobuterol, is simple to operate, is environmentally friendly, is low in cost and is suitable for industrial production.