64100-61-4

Upstream product

• 54340-62-4 bufuralol 
• 75-64-9 tert-butylamine 
• 537693-72-4 (S)-(+)-2-chloro-1-(7-ethylbenzofuran-2-yl)ethanol 
• 593266-85-4 2-bromo-1-(7-ethyl-benzofuran-2-yl)ethanone 
• 1256291-77-6 2-(tert-butylamino)-1-(7'-ethylbenzofuran-2'-yl)ethanone 
• 73289-91-5 2-hydroxy-3-ethylbenzaldehyde 
• 59664-03-8 1-(7-ethylbenzofuran-2-yl)ethanone 
• 90-00-6 o-Hydroxyethylbenzene 
• 69543-74-4 2-chloro-1-(7-ethyl-benzofuran-2-yl)ethanone 

Downstream Products

• 64100-62-5 (-)-Bufuralol 
• 61470-08-4 4-Hydroxy-Bufuralol 
• 97733-09-0 3-tert-butyl-5(R)-<7-(1-hydroxyethyl)-2-benzofuranyl>-oxazolidinone 
• 97733-13-6 5(R)-(7-acetyl-2-benzofuranyl)-3-tert-butyl-2-oxazolidinone 
• 57704-16-2 (+)-(1R,1'RS)-Hydroxybufuralol 
• 84952-27-2 2-<2-(tert-butylamino)-1(R)-hydroxyethyl>-7-benzofuranyl methyl ketone 
• 97749-44-5 3-tert-butyl-5(R)-(7-ethyl-2-benzofuranyl)-2-oxazolidinone 

Relevant academic research and scientific papers

Enantioselective and diastereoselective hydroxylation of bufuralol. Absolute configuration of the 7-(1-hydroxyethyl)-2-[1-hydroxy-2-(tert-butylamino)ethyl]benzofurans, the benzylic hydroxylation metabolites

Asymmetric synthesis of the diastereomeric 7-(1-hydroxyethyl)-2-[1-hydroxy-2-(tert-butylamino)ethyl]benzofurans (2), the benzylic hydroxylation metabolites of bufuralol (1), is described, and the absolute configurations of these diastereomers are assigned. 1''-Oxobufuralol (3) was reduced with a complex of (2S)-(-)-2-amino-3-methyl-1,1-diphenylbutan-1-ol and borane, yielding 2, which had a 95:5 ratio of the possible 1''R and 1''S isomers as determined by HPLC. Separation of the resulting diastereomers was facilitated by derivatization with the enantiomers of 1-phenethyl isocyanate (PEIC). The absolute configurations 1'S.,''R and 1'R,1''R were assigned to the diastereomers formed in excess, 2c and 2b, on the basis of the known stereochemistry of reduction of closely related alkyl phenyl ketones to R alcohols by using this chiral borane reagent. The circular dichroism spectra of the four isomeric benzylic alcohols were in agreement with these assignments. In the presence of the rat liver microsomal fraction, benzylic hydroxylation of bufuralol was significantly product stereoselective favoring formation of diastereomers with the 1''R absolute stereochemistry at the new chiral center in products from (1'R)-1 by a ratio of 4.5:1 [(1'R,1''R)-2:(1'R,1''S)-2] and by nearly 8:1 [(1'S,1''R)-2:(1'S,1''S)-2] from (1'S)-1. (1'R)-Bufuralol was more rapidly hydroxylated than was (1'S)-1, by about 3-fold. In the presence of human liver microsomes, (1'R)-bufuralol was also more rapidly hydroxylated than was (1'S)-1, by ca. 2.5-fold. However, product stereoselectivity from the 1'R enantiomer was reversed from that observed in the rat liver microsomal oxidation, with more (1''S)-carbinol being formed than 1''R isomer by nearly 4-fold. From (1'S)-1, about equal amounts of the two possible hydroxybufuralol diastereomers were formed. The results from the human liver microsomal studies are consistent with observed enantioselectivity of hydroxylation of bufuralol in vivo in humans.

New chemo-enzymatic approaches for the synthesis of (R)- and (S)-bufuralol

Both enantiomers of bufuralol are pharmaceutically important molecules. While the (S)-isomer with a higher β-blocking activity is recommended for hypertension treatment, the (R)-enantiomer can be used as marker of hepatic activity. In this paper two new a

Asymmetric synthesis of β-amino alcohols by the transfer hydrogenation of α-keto imines

The asymmetric transfer hydrogenation of representative aryl and benzofuranyl 2-tert-butylaminoethanones with formic acid-triethylamine, catalyzed by RhCl[(R,R)-TsDPEN](C5Me5), produced the corresponding β-tert-butylamino alcohols in 97-99% ee. A short asymmetric synthesis of (R)-bufuralol, a potent β-adrenergic receptor antagonist, is described. This approach to β-amino alcohols from ketones circumvents the halogenation-reduction-amination sequence.

Enantioselective synthesis of (R)-bufuralol via dynamic kinetic resolution in the key step

(Figure presented) An enantioselective synthesis of (R)-bufuralol via a ruthenium- and enzyme-catalyzed dynamic kinetic resolution (DKR) has been achieved. The synthesis starts from readily available 2-ethylphenol and provides (R)-bufuralol in high ee and a good overall yield of 31%.

Chiral separations of some β-adrenergic agonists and antagonists on AmyCoat column by HPLC

Sixteen β-adrenergic antagonists namely acebutalol, alprenolol, atenolol, bisoprolol, bopindolol, bufurolol, carazolol, celiprolol, indenolol, metaprolol, nebivolol, oxprenolol, practolol, propranolol, tertalol, and timolol, and two β-adrenergic agonists namely cimeterol and clenbuterol were resolved on AmyCoat (150 x 46 mm, 3 μm size of silica particle) by using (85:15:0.1, v/v/v), (90:10:0.1, v/v/v), and (95:05:0.1, v/v/v) combinations of η-heptane, ethanol, and diethylamine solvents, respectively. The flow rates used were 0.5, 1.0, 2.0, and 3.0 ml/min with detection at 225 nm. The values of capacity, separation, and resolution factors ranged from 0.38 to 19.70, 1.08-2.33, and 1.0 and 4.50, respectively. The maximum and minimum resolutions were achieved for celiprolol and bufurolol, respectively. The chiral recognition mechanisms were also discussed. The values of validation parameters were calculated.

THERAPY FOR COMPLICATIONS OF DIABETES

A method for enhancing glycemic control and/or insulin sensitivity in a human subject having diabetic nephropathy and/or metabolic syndrome comprises administering to the subject a selective endothelin A (ETA) receptor antagonist in a glycemic control and/or insulin sensitivity enhancing effective amount. A method for treating a complex of comorbidities in an elderly diabetic human subject comprises administering to the subject a selective ETA receptor antagonist in combination or as adjunctive therapy with at least one additional agent that is (i) other than a selective ETA receptor antagonist and (ii) effective in treatment of diabetes and/or at least one of said comorbidities other than hypertension. A therapeutic combination useful in such a method comprises a selective ETA receptor antagonist and at least one antidiabetic, anti-obesity or antidyslipidemic agent other than a selective ETA receptor antagonist.

ANTIHYPERTENSIVE THERAPY

A new use of darusentan is provided in preparation of a pharmaceutical composition for lowering blood pressure in a patient exhibiting resistance to a baseline antihypertensive therapy with one or more drugs. The composition comprises darusentan in an amount providing a therapeutically effective daily dose; wherein (a) the composition is orally deliverable and/or (b) the daily dose of darusentan is effective to provide a reduction of at least about 3 mmHg in one or more blood pressure parameters selected from trough sitting systolic, trough sitting diastolic, 24-hour ambulatory systolic, 24-hour ambulatory diastolic, maximum diurnal systolic and maximum diurnal diastolic blood pressures. Further provided is a new use of darusentan in preparation of a pharmaceutical composition for lowering blood pressure in a patient exhibiting resistance to a baseline antihypertensive therapy, wherein the composition is administered adjunctively with at least one diuretic and at least one antihypertensive drug selected from ACE inhibitors, angiotensin II receptor blockers, beta-adrenergic receptor blockers and calcium channel blockers.

Method for treating resistant hypertension

A method is provided for lowering blood pressure in a patient having clinically diagnosed resistant hypertension. The method comprises administering darusentan to the patient adjunctively with a baseline antihypertensive regimen that comprises administration of at least one diuretic and at least two antihypertensive drugs selected from at least two of (a) ACE inhibitors and angiotensin II receptor blockers, (b) beta-adrenergic receptor blockers and (c) calcium channel blockers. The darusentan is orally administered at a dose and frequency effective, in combination with the baseline regimen, to provide a reduction of at least about 3 mmHg in one or more blood pressure parameters selected from trough sitting systolic, trough sitting diastolic, 24-hour ambulatory systolic, 24-hour ambulatory diastolic, maximum diurnal systolic and maximum diurnal diastolic blood pressures.

Enantioselective reduction of benzofuryl halomethyl ketones: Asymmetric synthesis of (R)-bufuralol

Enantioselective reduction of representative 2-(bromoacetyl)- and 2-(chloroacetyl)benzofurans with (-)-B-chlorodiisopinocampheylborane and by transfer hydrogenation with formic acid/triethylamine in the presence of RhCl[R,R-TsDPEN](C5Me5/

Synthesis of optically active methadones, LAAM and bufuralol by lipase-catalysed acylations

(R)- and (S)-Methadones and levo-α-acetylmethadol (LAAM) have been synthesised starting from lipase-catalysed acylation of dimethylaminopropan-2-ol. An approach to the synthesis of (R)-bufuralol is also presented.