88150-42-9Relevant articles and documents
Light-Induced Formation/Scission of C-N, C-O, and C-S Bonds Enables Switchable Stability/Degradability in Covalent Systems
Hai, Yu,Li, Ziyi,Lu, Hanwei,Ye, Hebo,You, Lei,Zou, Hanxun
supporting information, p. 20368 - 20376 (2021/12/03)
The manipulation of covalent bonds could be directed toward degradable, recyclable, and sustainable materials. However, there is an intrinsic conflict between properties of stability and degradability. Here we report light-controlled formation/scission of three types of covalent bonds (C-N, C-O, and C-S) through photoswitching between equilibrium and nonequilibrium states of dynamic covalent systems, achieving dual benefits of photoaddressable stability and cleavability. The photocyclization of dithienylethene fused aldehyde ring-chain tautomers turns on the reactivity, incorporating/releasing amines, alcohols, and thiols reversibly with high efficiency, respectively. Upon photocycloreversion the system is shifted to kinetically locked out-of-equilibrium form, enabling remarkable robustness of covalent assemblies. Reaction coupling allows remote and directional control of a diverse range of equilibria and further broadens the scope. Through locking and unlocking covalent linkages with light when needed, the utility is demonstrated with capture/release of bioactive molecules, modification of surfaces, and creation of polymers exhibiting tailored stability and degradability/recyclability. The versatile toolbox for photoswitchable dynamic covalent reactions to toggle matters on and off should be appealing to many endeavors.
Two validated stability-indicating chromatographic methods for the separation of two anti-hypertensive combinations in the presence of their degradation products or impurities
Samy Mostafa, Noha,AbdElHamid, Ghada,Elsayed Zaazaa, Hala,Mohamed Amer, Sawsan
, p. 2427 - 2439 (2019/07/16)
Two RP-HPLC methods were developed, optimized, and validated for the determination of two different anti-hypertensive combinations in the presence of their degradation products or impurities and in their pharmaceutical formulations. The first mixture is Ramipril (RAM) in combination with Amlodipine besylate (AML) [mixture I], while the second one is a combination of Ramipril (RAM), Atorvastatin (ATV), and Aspirin (ASP) [mixture II].The proposed combinations were successfully separated on X-bridge C18column (250 × 4.6?mm i.d, 5?μm p.s.), using a mobile phase of 0.05?M phosphate buffer-acetonitrile-THF (60:40:0.1% by volume) pH 2.5 and an isocratic mobile phase formed of acetonitrile-0.05?M phosphate buffer-THF (60:40:0.1% by volume) pH 2.5 for mixture (I) and (II) at a flow rate of 1?mL/min and 1.2?mL/min, respectively. The compromising components of the mixtures were detected at 218?nm. For the best separation of the mentioned components different parameters were examined and optimized. The two suggested methods were validated in compliance with the ICH guidelines and were successfully applied for the quantification of the cited components in presence of their obtained degradation products as well as in their commercial pharmaceutical formulations. For both methods the obtained results were statistically analyzed and compared to those of the official and reported methods; using Student’s t test and F test showing no significant difference with high accuracy and good precision.
ANTIHYPERTENSIVE THERAPY
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, (2009/09/08)
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.