590410-69-8

Upstream product

• 94749-73-2 6-bromohexyl 4-phenylbutyl ether 
• 1761-61-1 5-bromosalicyclaldehyde 
• 54030-33-0 2,2-dimethyl-4H-benzo[d][1,3]dioxin-6-carboxaldehyde 
• 2316-64-5 5-bromo-2-hydroxybenzyl alcohol 
• 123-08-0 4-hydroxy-benzaldehyde 
• 53412-47-8 3-(chloromethyl)-4-hydroxybenzaldehyde 
• 54030-32-9 4-hydroxy-3-(hydroxymethyl)benzaldehyde 
• 208924-99-6 (R)-1-(2,2-dimethyl-4H-benzo[d][1,3]dioxin-6-yl)-2-nitroethanol 
• 208925-08-0 (2R)-hydroxy-2-(2,2-dimethyl-4H-1,3-benzodioxine-6-yl)-ethylamine 
• 52113-69-6 6-bromo-2,2-dimethyl-4H-benzo[1,3]dioxine 
• 1067185-92-5 (R)-2-(benzyl(6-(4-phenylbutoxy)hexyl)amino)-1-(2,2-dimethyl-4H-benzo[d][1,3]dioxin-6-yl)ethanol 
• 97664-54-5 6-(4-phenylbutoxy)hexanal 
• 452339-70-7 di-(tert-butyl) 2-(2,2-dimethyl-4H-1,3-benzodioxin-6-yl)-2-oxoethyliminodicarbonate 
• 452339-72-9 tert-butyl (2R)-2-(2,2-dimethyl-4H-1,3-benzodioxin-6-yl)-2-hydroxyethylcarbamate 

Downstream Products

• 135271-47-5 (R)-(-)-salmeterol 
• 135271-47-5 (S)-Salmeterol 

Relevant academic research and scientific papers

Structure-Guided Tuning of a Hydroxynitrile Lyase to Accept Rigid Pharmaco Aldehydes

The chiral vicinal C-O/C-N bifunctional groups generated from enzymatic hydrocyanation represents a useful methodology. However, construction of the pharmacophore of β2-adrenoreceptor agonists with this method remains a great challenge because of complete racemization of the benzylic alcohol during deprotection of the acetal groups. In this study, structure-guided redesign of a hydroxynitrile lyase originating from Prunus communis (PcHNL5) enables a highly enantioselective hydrocyanation of rigid benzo-ketal aldehyde which was proved to be resistant against racemization during the deprotection step, with dramatically improved productivity (>95% conversion vs 2-adrenoreceptor agonist, in an optically pure form (>99% ee) with an overall yield of 54%, which is the highest value reported.

Enantioselective synthesis of (R)-salmeterol employing an asymmetric Henry reaction as the key step

A practical synthesis of (R)-salmeterol has been accomplished from 3-bromo salicylaldehyde, which involved a Cu(II)-sparteine complex catalyzed asymmetric Henry reaction as the key step. (R)-Salmeterol can be obtained in 39% overall yield and 95% ee.

A convenient synthesis of (R)-salmeterol via Rh-catalyzed asymmetric transfer hydrogenation

(R)-Salmeterol was synthesized in eight steps with salicaldehyde as the starting material. The key chiral intermediate, alcohol 5, was prepared via Rh-catalyzed asymmetric transfer hydrogenation with (S,S)-PEG-BsDPEN or (S,S)-TsDPEN ligand and sodium formate as the hydrogen donor under mild conditions.

Potassium trimethylsilanolate induced cleavage of 1,3-oxazolidin-2- and 5-ones, and application to the synthesis of (R)-salmeterol.

A convenient and efficient method for the cleavage of 1,3-oxazolidin-5-ones and 1,3-oxazolidin-2-ones utilising potassium trimethylsilanolate in tetrahydrofuran is described. The benzyloxycarbonyl-protecting group is readily removed under the reaction conditions, whereas the N-benzoyl group is stable. A synthesis of (R)-salmeterol exploiting the 2-oxazolidinone ring as a protecting group for the ethanolamine moiety is also described.

A mild, enantioselective synthesis of (R)-salmeterol via sodium borohydride-calcium chloride asymmetric reduction of a phenacyl phenylglycinol derivative

A short and efficient enantioselective route to (R)-salmeterol involving asymmetric reduction of a phenylglycinyl ketone derivative followed by reductive amination of the resulting amino alcohol and hydrogenolysis is described.