153225-88-8Relevant articles and documents
A new (R)-hydroxynitrile lyase from Prunus mume: Asymmetric synthesis of cyanohydrins
Nanda, Samik,Kato, Yasuo,Asano, Yasuhisa
, p. 10908 - 10916 (2007/10/03)
A new hydroxynitrile lyase (HNL) was isolated from the seed of Japanese apricot (Prunus mume). The enzyme has similar properties with HNL isolated from other Prunus species and is FAD containing enzyme. It accepts a large number of unnatural substrates (benzaldehyde and its variant) for the addition of HCN to produce the corresponding cyanohydrins in excellent optical and chemical yields. A new HPLC based enantioselective assay technique was developed for the enzyme, which promotes the addition of KCN to benzaldehyde in a buffered solution (pH=4.5).
Synthesis of the Adrenergic Bronchodilators (R)-Terbutalinel and (R)-Salbutamol from (R)-Cyanohydrins
Effenberger, Franz,Jaeger, Juergen
, p. 3867 - 3873 (2007/10/03)
Stereoselective syntheses of (R)-terbutaline and (R)-salbutamol acetal, which are important bronchodilators, starting from O-protected (R)-cyanohydrins are described. (R)-Terbutaline hydrochloride (R)-9·HCl is obtained in an overall yield of 44% with >98% ee from the O-bisallyl-protected cyanohydrin (R)-4k via a Ritter N-tertiary butylation to the amide (R)-6a, hydrogenation to the amino alcohol (R)-7a, and deprotection of the hydroxyl functions. (R)-Salbutamol acetals (R)-7b,c can be obtained from the corresponding O-protected (R)-cyanohydrins either via the route described for (R)-terbutaline or via selective hydrogenation of the protected cyanohydrin (R)-11 to the imino derivative, transimination with tert-butylamine, followed by hydrogenation with NaBH4 to give the 2-amino alcohol derivative (R)-12. Desilylation of (A)-12 to (R)-7c is performed with LiAlH4. Hydrolytic cleavage of the acetals (A)-7b and c to (R)-salbutamol was not yet possible without racemization.
Substituent Effects on the Enantioselective Hydrocyanation of Aryl Aldehydes
Kim, Hyun J.,Jackson, W. Roy
, p. 1541 - 1548 (2007/10/02)
A detailed study of the dipeptide catalysed enantioselective hydrocyanation of a series of O-substituted 4-hydroxybenzaldehydes has shown that adverse steric effects can occur leading to low enantiomeric excess (e.e.) values when the substituent is long and flexible.Similar hydrocyanation of several derivatives of 3,4-dihydroxybenzaldehydes have been shown to give very variable values of e.e.Hydrocyanation of 3,5-dimethoxy and 3,4,5-trimethoxybenzaldehyde consistently gave low values of e.e.
Synthetic applications of optically active cyanohydrins. Enantioselective syntheses of the hydroxyamides tembamide and aegeline, the cardiac drug denopamine, and some analogues of the bronchodilator salbutamol
Brown, Roger F. C.,Donohue, Andrew C.,Roy Jackson,McCarthy, Tom D.
, p. 13739 - 13752 (2007/10/02)
The natural hydroxyamides, (-)-tembamide and (-)-aegeline, and the cardiac drug (-) -denopamine have been prepared in homochiral form in good overall yield (>65%) from para - methoxy or para-allyloxybenzaldehyde by synthetic sequences involving entantioselective hydrocyanation of the aldehydes. Similar chemistry has been used to prepare analogues of the bronchodilator (-)-salbutamol both in high yield and with good enantiomeric excess.
A Synthesis of (-)-Denopamine
Brown, Roger F. C.,Jackson, W. Roy,McCarthy, Tom D.
, p. 2149 - 2150 (2007/10/02)
The important cardiac drug, (-)-denopamine, has been synthesized in 68percent overall yield from para-allyloxybenzaldehyde via (R)-2-hydroxy-2-acetonitrile.
