- Efficient chemoenzymatic synthesis of (RS)-, (R)-, and (S)-bunitrolol
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A new chemical and the first chemoenzymatic synthesis of β-adrenergic receptor blocking agent bunitrolol is reported in racemic (RS) and enantioenriched forms (R and S). The intermediates (R)- and (S)-1-chloro-3-(2- cyanophenoxy)propan-2-ol intermediates were synthesized from the corresponding racemic alcohol through enzymatic kinetic resolution. The commercial available lipases PS-C and CCL exhibited complementary enantioselectivity during transesterification of the racemic alcohol with vinyl acetate affording the (R)-alcohol along with (S)-acetate and the (S)-alcohol along with (R)-acetate, respectively, and represent an example of enzymatic switch for reversal of enantioselectivity. The effects of various reaction parameters, such as temperature, time, substrate and enzyme concentration, and reaction medium, on the activity and enantioselectivity were optimized. The (R)- and (S)-alcohols were converted into (S)-and and (R)-bunitrolol, respectively, by treatment with tert-butylamine. The (R)- and (S)-acetates, obtained enzymatically were deacetylated to the corresponding alcohol by chemical hydrolysis and further converted into (S)-and and (R)-bunitrolol by chemical means. This is the first chemoenzymatic synthesis of both of the enantiomers of the drug. (RS)-, (R)-, and (S)-Bunitrolol were also synthesized following the 'all chemical' routes from (RS)-, (R)-, and (S)-epichlorohydrin via the corresponding (RS)-, (S)-, and (R)-2-cyanoglycidyl ether and the (RS)-, (R)-, and (S)-1-chloro-3-(2- cyanophenoxy)propan-2-ol intermediates with improved overall yields and better enantiomeric excesses compared to the reported processes.
- Banoth, Linga,Chandarrao, Bhukya,Pujala, Brahmam,Chakraborti, Asit K.,Banerjee
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p. 479 - 488
(2014/03/21)
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- THERAPY FOR COMPLICATIONS OF DIABETES
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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.
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- ANTIHYPERTENSIVE THERAPY
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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.
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- Method for treating resistant hypertension
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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.
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- Retard form of pharmaceuticals with insoluble porous diffusion coatings
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A pharmaceutical dosage unit retard form having a constant, pH-independent release rate of active ingredient, consisting of a core comprising an active ingredient, and a semi-permeable diffusion coating over the core, were the coating consists of a water-insoluble film-former, a water-soluble polymer and eventually an acid-insoluble polymer incorporated therein.
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- Enteric coated mixture of 4-(2-hydroxy-3-isopropylamino-propoxy) indole and sodium lauryl sulphate
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The present invention provides a pharmaceutical composition for controlled release of 4-(2-hydroxy-3-isopropylamino-propoxy) indole in the intestinal tract, admixed with sodium lauryl sulphate, and enteric coated.
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- Therapeutic compositions and method
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A composition having bradycardia and isoproterenol antagonistic activity comprising at least one compound selected from the group consisting of racemates of 1-phenoxy-2-hydroxy-3-tert.-butylamino propanes of the formula EQU1 wherein R is selected from the group consisting of --(CH2)x --CN where x is an integer from 0 to 3, COOH and COOR' where R' is alkyl of 1 to 4 carbon atoms; R1 is selected from the group consisting of hydrogen, alkoxy and alkylthio of 1 to 4 carbon atoms, --CN and alkenyl and alkynyl of 2 to 4 carbon atoms and R2 is selected from the group consisting of hydrogen, halogen and alkyl and alkoxy of 1 to 4 carbon atoms, their optically active isomers and their non-toxic, pharmaceutically acceptable acid addition salts of said racemates and said optically active isomers and a major amount of a pharmaceutical carrier and a method of producing bradycardia and suppressing tachycardia effects of N-isopropyl-noradrenaline in warm-blooded animals.
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