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Tomislav Friscic - One of the best experts on this subject based on the ideXlab platform.
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mechanosynthesis of pharmaceutically relevant sulfonyl thio ureas
ChemInform, 2014Co-Authors: Davin Tan, Vjekoslav Strukil, Cristina Mottillo, Tomislav FriscicAbstract:The first application of mechanochemistry to conduct the synthesis of sulfonyl-(thio)ureas (III), (VI), and (X), including antidiabetic drugs tolbutamide, Chlorpropamide (VIa) and glibenclamide (X) by either stoichiometric base-assisted or Cu-catalyzed coupling of sulfonamides and iso(thio)cyanates, is reported.
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mechanosynthesis of pharmaceutically relevant sulfonyl thio ureas
Chemical Communications, 2014Co-Authors: Davin Tan, Vjekoslav Strukil, Cristina Mottillo, Tomislav FriscicAbstract:We demonstrate the first application of mechanochemistry to conduct the synthesis of sulfonyl-(thio)ureas, including known anti-diabetic drugs tolbutamide, Chlorpropamide and glibenclamide, in good to excellent isolated yields by either stoichiometric base-assisted or copper-catalysed coupling of sulfonamides and iso(thio)cyanates.
Elena V Boldyreva - One of the best experts on this subject based on the ideXlab platform.
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the role of fluids in high pressure polymorphism of drugs different behaviour of β Chlorpropamide in different inert gas and liquid media
RSC Advances, 2016Co-Authors: Boris A Zakharov, Yurii V Seryotkin, Nikolay Tumanov, Damian Paliwoda, M Hanfland, Alexander Kurnosov, Elena V BoldyrevaAbstract:The hydrostatic compression of β-Chlorpropamide gives different high-pressure phases, depending on the choice of pressure-transmitting fluid (paraffin, neon and helium). This is particularly surprising as none of these fluids interact obviously with the solid at ambient pressure. This phenomenon is not related to dissolution and recrystallization, in contrast to what has been previously observed for β-Chlorpropamide in a 1 : 1 pentane–isopentane mixture.
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hedvall effect in cryogrinding of molecular crystals a case study of a polymorphic transition in Chlorpropamide
CrystEngComm, 2011Co-Authors: Tatiana N Drebushchak, A A Ogienko, Elena V BoldyrevaAbstract:The effect of grinding at ambient temperature and at 77 K (CryoMill Retsch) on the polymorphic transitions in α- and e- Chlorpropamide has been compared. The result of grinding of α-Chlorpropamide at room temperature could not be interpreted as a mere formation of traces of the e-polymorph. The diffraction patterns suggested the presence of small amounts of some unknown polymorph, possibly in a mixture with other polymorph(s). Possibly, mechanical treatment gave a defect nanostructured phase with alternating domains. Cryogrinding of α-Chlorpropamide did not result in polymorphic transitions. In contrast, cryogrinding of the e-polymorph was much more efficient than grinding at ambient temperature: almost no changes could be observed at ambient temperature, whereas cryogrinding gave the α-form. The observed phenomena could be interpreted taking into account that at low temperatures the e-polymorph undergoes a polymorphic transition into another polymorph— the e′-form. Without grinding, the e′-form transforms back to the e-polymorph when heated back to ambient temperature. If grinding takes place in the temperature range of the e- to e′-polymorphic transition, the transformation to the α-form occurs. One phase transition, induced by low temperature, facilitates another one, induced by mechanical treatment. The reason for this interesting phenomenon is to be sought in the similarity of the crystal packing of molecules with different molecular conformations in the e- and e′-forms, and of the similarity of the molecular conformations despite different crystal packing in the e′- and α-forms.
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two polymorphs of Chlorpropamide the delta form and the high temperature epsilon form
Acta Crystallographica Section C-crystal Structure Communications, 2008Co-Authors: Elena V Boldyreva, N V Chukanov, Tatiana N DrebushchakAbstract:The epsilon-form of Chlorpropamide [systematic name: 4-chloro-N-(propylaminocarbonyl)benzenesulfonamide], C(10)H(13)ClN(2)O(3)S, has been obtained as single crystals from solution (and not as a polycrystalline sample by heating the alpha-, gamma- or delta-forms). The results of anisotropic structure refinements for the epsilon- and delta-forms are reported. The density of the delta-polymorph is the highest, and that of the epsilon-polymorph the lowest, among the five known Chlorpropamide polymorphs. The main intermolecular hydrogen-bonding pattern in polymorphs delta and epsilon is the same as in polymorphs alpha, beta and gamma, but the conformations differ. The densities of the polymorphs were found to depend on the molecular conformations.
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ft ir and ft raman spectra of five polymorphs of Chlorpropamide experimental study and ab initio calculations
Journal of Molecular Structure, 2008Co-Authors: Yu A Chesalov, Elena V Boldyreva, T N Drebushchak, V P Baltakhinov, N V Chukanov, V A DrebushchakAbstract:Abstract IR- and Raman spectra were studied for five polymorphs of Chlorpropamide (α, β, γ, δ and e) (phase purity proved by DSC, X-ray single-crystal and powder diffraction). The equilibrium geometry and the vibrational spectra for different molecular conformations were calculated ab initio (DFT, B3LYP approximation). The assignment of the vibrational bands was made on the basis of the theoretical calculations and a comparison of the experimentally measured spectra for the crystalline polymorphs and the melt. The differences in the experimental vibrational spectra of the five Chlorpropamide polymorphs were correlated with the X-ray structural data, and shown to be mainly due to the intermolecular interactions effect, and only to a smaller extent – to the conformational changes.
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effect of pressure up to 5 5gpa on dry powder samples of Chlorpropamide form a
International Journal of Pharmaceutics, 2006Co-Authors: Elena V Boldyreva, Vladimir Dmitriev, Bruno C HancockAbstract:Abstract The effect of pressure up to 5.5 GPa on a dry powder sample of Chlorpropamide (4-chloro- N -((propylamino)-carbonyl)-benzenesulfonamide), form-A (sp. gr. P 2 1 2 1 2 1 , a = 9.066 A, b = 5.218 A, c = 26.604 A), was studied in situ in a Merrill–Bassett diamond anvil cell using high-resolution X-ray powder diffraction (a synchrotron radiation source at SNBL ESRF, Grenoble). No evidence of the polymorphic transformation of Chlorpropamide form-A to form-C was observed. The A–C polymorphic transition on tabletting previously reported by Otsuka et al. (1989) is therefore likely to be due to local heating effects. Similarly, the phase transitions of form-A reported by Cao (2002) to be induced by pressure applied to a sample in its saturated ethanol solution (at 0.9 and at 2.0 GPa) would appear to be solvent-mediated. In the dry sample, a phase transition may be supposed to occur at pressures above 4 GPa, but this requires further studies.
Davin Tan - One of the best experts on this subject based on the ideXlab platform.
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mechanosynthesis of pharmaceutically relevant sulfonyl thio ureas
ChemInform, 2014Co-Authors: Davin Tan, Vjekoslav Strukil, Cristina Mottillo, Tomislav FriscicAbstract:The first application of mechanochemistry to conduct the synthesis of sulfonyl-(thio)ureas (III), (VI), and (X), including antidiabetic drugs tolbutamide, Chlorpropamide (VIa) and glibenclamide (X) by either stoichiometric base-assisted or Cu-catalyzed coupling of sulfonamides and iso(thio)cyanates, is reported.
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mechanosynthesis of pharmaceutically relevant sulfonyl thio ureas
Chemical Communications, 2014Co-Authors: Davin Tan, Vjekoslav Strukil, Cristina Mottillo, Tomislav FriscicAbstract:We demonstrate the first application of mechanochemistry to conduct the synthesis of sulfonyl-(thio)ureas, including known anti-diabetic drugs tolbutamide, Chlorpropamide and glibenclamide, in good to excellent isolated yields by either stoichiometric base-assisted or copper-catalysed coupling of sulfonamides and iso(thio)cyanates.
Takako Ishiguro - One of the best experts on this subject based on the ideXlab platform.
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crystallization and polymorphic transitions of Chlorpropamide in aqueous 2 hydroxybutyl β cyclodextrin solution
European Journal of Pharmaceutical Sciences, 2010Co-Authors: Takako Ishiguro, Fumitoshi Hirayama, Daisuke Iohara, Hidetoshi Arima, Kaneto UekamaAbstract:Effects of cyclodextrins on crystallization of Chlorpropamide and the polymorphic transition mechanism of the drug in aqueous solution were investigated. In the presence of 2-hydroxybutyl-beta-cyclodextrin, Chlorpropamide was exclusively crystallized to metastable Form II and III polymorphs, whereas it was crystallized to stable Form A in the absence of the beta-cyclodextrin at 4 degrees C. The crystallization to metastable Form II or III polymorph was dependent upon 2-hydroxybutyl-beta-cyclodextrin concentrations employed, i.e. crystallization to Form III at a lower concentration (0.5 mM), whereas to Form II in a higher concentration (5 mM). At an intermediate concentration (2 mM), the least stable Form II crystal was initially precipitated, but it was transformed to Form III crystal. At higher temperature, Form III crystal was converted to stable Form A crystal. In aqueous solution, Chlorpropamide crystallized to stable Form A crystal consecutively through metastable Forms II and III, according to "Ostwald's Rule of Stages". 2-Hydroxybutyl-beta-cyclodextrin inhibits the transition of Form II to Form III at higher concentrations and that of Form III to Form A at lower concentrations. The results suggest that 2-hydroxybutyl-beta-cyclodextrin is useful for selective preparation of metastable Chlorpropamide polymorphs occurring during crystallization according to the Ostwald's rule.
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prominent inhibitory effect of 2 hydroxybutyl β cyclodextrin on solution mediated polymorphic transition of Chlorpropamide
Chemistry Letters, 2008Co-Authors: Takako Ishiguro, Fumitoshi Hirayama, Daisuke Iohara, Kaneto UekamaAbstract:The effects of cyclodextrins on crystallization of Chlorpropamide from aqueous solutions were investigated. Parent α-, β-, and γ-cyclodextrins and 2-hydroxypropyl-α-, and -β-cyclodextrins and gluco...
Juliano L. Sartoretto - One of the best experts on this subject based on the ideXlab platform.
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the influence of improved glycaemic control with Chlorpropamide on microvascular reactivity and nitric oxide synthase activity in diabetic rats
Journal of Pharmacy and Pharmacology, 2010Co-Authors: Juliano L. Sartoretto, Robson A.s. Santos, Dorothy Nigro, Roberto Kenji Nakamura Cuman, M. H. C. Carvalho, Cristoforo Scavone, Rita C Tostes, Z B FortesAbstract:Hyperglycaemia is a primary cause of vascular complications in diabetes. A hallmark of these vascular complications is endothelial cell dysfunction, which is partly due to reduced production of nitric oxide. The aim of this study was to verify the influence of improved glycaemic control with Chlorpropamide on microvascular reactivity, endothelial nitric oxide synthase (e-NOS) expression, and NOS activity in neonatal streptozotocin-induced diabetic rats (n-STZ). Diabetes was induced by STZ injection into neonates Wistar rats. n-STZ diabetic rats were treated with Chlorpropamide (200 mg kg -1 , 15 days, by gavage). The changes in mesenteric arteriolar and venular diameters were determined in anaesthetized control and n-STZ diabetic rats, before and after topical application of acetylcholine, bradykinin and sodium nitroprusside (SNP). We also assessed e-NOS expression (using polymerase chain reaction after reverse transcription of mRNAs into cDNAs) and NOS activity (conversion of L-arginine to citrulline) in the mesenteric vascular bed of Chlorpropamide-treated n-STZ, vehicle-treated n-STZ, and control rats. In n-STZ, Chlorpropamide treatment reduced high glycaemic levels, improved glucose tolerance and homoeostatic model assessment (HOMA-beta), and restored NOS activity. Impaired vasodilator responses of arterioles and venules to acetylcholine, bradykinin and SNP were partially corrected by Chlorpropamide treatment in n-STZ. We concluded that improved metabolic control and restored NOS activity might be collaborating with improved microvascular reactivity found in Chlorpropamide-treated n-STZ.
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Chlorpropamide treatment restores the reduced carrageenan-induced paw edema and pleural exudate volume in diabetic rats
Inflammation research : official journal of the European Histamine Research Society ... [et al.], 2008Co-Authors: Juliano L. Sartoretto, Gessilda De Alcantara Nogueira De Melo, Ciomar Aparecida Bersani-amado, M. A. Oliveira, Robson A.s. Santos, Rita De Cássia Aleixo Tostes Passaglia, Dorothy Nigro, Roberto Kenji Nakamura Cuman, M. H. C. Carvalho, Zuleica Bruno FortesAbstract:Knowing that hyperglycemia is a hallmark of vascular dysfunction in diabetes and that neonatal streptozotocin-induced diabetic rats (n-STZ) present reduced inflammatory response, we decided to evaluate the effect of Chlorpropamide-lowered blood glucose levels on carrageenan-induced rat paw edema and pleural exudate in n-STZ. Diabetes was induced by STZ injection (160 mg/kg, ip) in neonates (2-day-old) Wistar rats. n-STZ diabetic rats were treated with Chlorpropamide (200mg/kg, 15d, by gavage) 8 weeks after STZ injection. Carrageenan-induced paw edema and pleural exudate volumes were assessed concomitantly with peripheral and exudate leukocyte count. We also evaluated the expression of inducible nitric oxide synthase (iNOS) in lungs of all experimental groups. Chlorpropamide treatment improved glucose tolerance, β-cell function (assessed by HOMA-β), corrected paw edema, and pleural exudate volume in n-STZ. Neither leukocyte count nor iNOS expression were affected by diabetes or by Chlorpropamide treatment. Chlorpropamide treatment by restoring β-cell function, reducing blood sugar levels, and improving glucose tolerance might be contributing to the correction of the reduced inflammatory response tested as paw edema and pleural exudate in n-STZ diabetic rats.