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Hydrochloride Salt (hydrochloride + salt)
Selected AbstractsCoupling of Carbon Dioxide with Epoxides Catalyzed by Amino Acid Hydrochloride SaltsCHINESE JOURNAL OF CHEMISTRY, Issue 7 2008Huan-Feng JIANG Abstract Using amino acid hydrochloride salt as a catalyst, the coupling reaction of CO2 with epoxides could proceed smoothly to give cyclic carbonates in very good yields and high selectivity. The reaction conditions such as the pressure of carbon dioxide, reaction temperature, time and catalyst loading were carefully investigated. [source] An efficient synthesis of [13C6]-3,5-dichloroanilineJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 7 2008Bachir Latli Abstract 3,5-Dichloroaniline is commonly found in many compounds with pharmacological and other biological activities. [13C6]-Aniline or its hydrochloride salt was converted in three steps to [13C6]-3,5-dichloroaniline, which can be incorporated in compounds of interest and used as internal standards in drug metabolism and pharmacokinetics (DMPK) studies. Copyright © 2008 John Wiley & Sons, Ltd. [source] Synthesis of 14C-labelled EM-800 (SCH 57050) and EM-652·HCl (SCH 57068·HCl, acolbifene), pure selective estrogen receptor modulatorsJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 11 2004Jean-Yves Sancéau Abstract EM-800 (SCH 57050) and EM-652·HCl (SCH 57068·HCl, acolbifene) are orally active pure selective estrogen receptor modulators. The corresponding 14C2 -radiolabelled compounds 1 and 2 were synthesized for metabolic studies with uniform labelling of two carbons within the benzene ring of the 2H-1-benzopyran moiety by optical resolution of racemic (±)-[14C2]EM-343 4. This pivotal intermediate amine was prepared in 6 steps with 38% yield from commercially available [U- 14C2]resorcinol (3). Resolution by selective crystallization of the diastereomeric mixture of (S)-(+)-camphorsulfonates salts gave the desired (+)-[14C2]EM-652·(+)-CSA 13. Moreover, the racemic amine 4 was recovered from mother liquors by basic treatment, and resolved again. We obtained salt 13, at a 52% yield with 97% diastereomeric excess by repeating the resolution,racemization process. Finally, the corresponding dipivaloate (+)-[14C2]EM-800 1 and hydrochloride salt (+)-[14C2]EM-652·HCl 2 were prepared at respective specific activities of 19.7 and 24.5 µCi/mg with 96.3% radiochemical purity. Copyright © 2004 John Wiley & Sons, Ltd. [source] Synthesis of morphine-[N -methyl- 14C]-6- , - D -glucuronideJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 2 2002John R. Ferguson Abstract Protected morphine-6-glucuronide was converted into morphine-[N -methyl- 14C]-6-glucuronide by a three-step procedure. Methyl (3-pivaloylmorphin-6-yl 2,3,4-tri- O -isobutyryl- , -D-glucopyranosid)uronate was N-demethylated by treatment with 1-chloroethyl chloroformate to afford protected normorphine-6-glucuronide as its hydrochloride salt. The normorphine-6-glucuronide derivative was alkylated with iodomethane-[14C] in the presence of potassium carbonate to produce C-14 labelled protected morphine-6-glucuronide. Finally, hydrolysis of the protecting groups using 5% sodium hydroxide solution gave morphine-[N -methyl- 14C]-6- , -D-glucuronide with a specific activity of 41.8 mCi mmol,1 and radiochemical purity of 99.2% (HPLC). Copyright © 2002 John Wiley & Sons, Ltd. [source] Effect of chloride ion on dissolution of different salt forms of haloperidol, a model basic drugJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 10 2005Shoufeng Li Abstract The effect of chloride ion (Cl,) on dissolution rates of hydrochloride, mesylate (methanesulfonate) and phosphate salt forms of a model drug, haloperidol, was investigated. The dissolution rates of the salts in 0.01M HCl from rotating disks followed the order of mesylate,,,phosphate,>,hydrochloride. With additional chloride ion, a decrease in dissolution rate of the hydrochloride salt was observed due to the common ion effect. Dissolution rates of mesylate and phosphate salts also decreased due to their conversion to the HCl salt form on the surfaces of dissolving disks, however, the dissolution rates of mesylate and phosphate salts under identical chloride ion concentrations were still higher than that of the HCl salt. In powder dissolution studies, it was observed that kinetics of nonhydrochloride-to-hydrochloride salt conversion play a major role in dissolution; the mesylate dissolved completely (<5 min) before its dissolution rate could be impeded by its conversion to the hydrochloride salt form. Therefore, despite the potential for conversion to a hydrochloride salt form, certain nonhydrochloride salt forms may still be preferred for dosage form development due to kinetic advantages during dissolution, such as higher apparent dissolution rate of a nonhydrochloride salt before it could completely convert to the hydrochloride form. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 94:2224,2231, 2005 [source] Selective Inclusion of Electron-Donating Molecules into Porphyrin Nanochannels Derived from the Self-Assembly of Saddle-Distorted, Protonated Porphyrins and Photoinduced Electron Transfer from Guest Molecules to Porphyrin DicationsCHEMISTRY - A EUROPEAN JOURNAL, Issue 31 2007Takahiko Kojima Prof. Abstract A doubly protonated hydrochloride salt of a saddle-distorted dodecaphenylporphyrin (H2DPP), [H4DPPP]Cl2, forms a porphyrin nanochannel (PNC). X-ray crystallography was used to determine the structure of the molecule, which revealed the inclusion of guest molecules within the PNC. Electron-donating molecules, such as p -hydroquinone and p -xylene, were selectively included within the PNC in sharp contrast to electron acceptors, such as the corresponding quinones, which were not encapsulated. This result indicates that the PNC can recognize the electronic character and steric hindrance of the guest molecules during the course of inclusion. ESR measurements (photoirradiation at ,>340,nm at room temperature) of the PNC that contains p -hydroquinone, catechol, and tetrafluorohydroquinone guest molecules gave well-resolved signals, which were assigned to cation radicals formed without deprotonation based on results from computer simulations of the ESR spectra and density functional theory (DFT) calculations. The radicals are derived from photoinduced electron transfer from the guest molecules to the singlet state of H4DPP2+. Transient absorption spectroscopy by femtosecond laser flash photolysis allowed us to observe the formation of 1(H4DPP2+)*, which is converted to H4DPP+. by electron transfer from the guest molecules to 1(H4DPP2+)*, followed by fast disproportionation of H4DPP+., and charge recombination to give diamagnetic species and the triplet excited state 3(H4DPP2+)*, respectively. [source] Coupling of Carbon Dioxide with Epoxides Catalyzed by Amino Acid Hydrochloride SaltsCHINESE JOURNAL OF CHEMISTRY, Issue 7 2008Huan-Feng JIANG Abstract Using amino acid hydrochloride salt as a catalyst, the coupling reaction of CO2 with epoxides could proceed smoothly to give cyclic carbonates in very good yields and high selectivity. The reaction conditions such as the pressure of carbon dioxide, reaction temperature, time and catalyst loading were carefully investigated. [source] Synthesis and activity of four (N,N -dimethylamino)benzamide nonsteroidal anti-inflammatory drugs based on thiazole and thiazolineJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 1 2006Daniel E. Lynch Four compounds derived from 2-aminothiazole and 2-amino-2-thiazoline were prepared by coupling the respective bases with the acid chlorides of either 3- or 4-(N,N -dimethylamino)benzoic acid. Products were identified using infrared spectroscopy, 1H NMR spectroscopy and electrospray mass spectroscopy and in two cases by single-crystal X-ray diffraction. Of the four, N -(thiazol-2-yl)-3-(N,N -dimethylamino)-benzamide (1), N -(thiazolin-2-yl)-4-(N,N -dimethylamino)benzamide (2), N -(thiazolin-2-yl)-3-(N,N -dimethylamino) benzamide (3) and N -(thiazolin-2-yl)-4-(N,N -dimethylamino)benzamide (4), the hydrochloride salts of compounds 3 and 4 showed anti-inflammatory activity across a concentration range of 10,2,5 × 10,4M while 3 (at a concentration of 10,5M) was found to have no adverse effect on myocardial function. The X-ray crystal structure of 2 and the 1:1 adduct structure of 3 with 3-(N,N -dimethylamino)benzoic acid are reported. [source] Raman spectra of putrescine, spermidine and spermine polyamines and their N -deuterated and N -ionized derivativesJOURNAL OF RAMAN SPECTROSCOPY, Issue 5 2003A. M. Amorim da Costa Abstract The experimental and calculated Raman spectra of the N -hydrogenated and N -deuterated biogenic polyamines putrescine, spermidine and spermine and of their N -hydrogenated and N -deuterated hydrochloride salts in the 2000,3400 cm,1 spectral region (at distinct temperatures) are reported and analysed. A complete assignment of the N,H, C,H and N,D stretching modes is carried out, in the light of both steric and hydrogen-bonding interactions on the conformational behaviour of these systems. Copyright © 2003 John Wiley & Sons, Ltd. [source] The hydrated and anhydrous gold(III) tetrachloride salts of l -ecgonine, an important forensic toxicology marker for cocaineACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2010Matthew R. Wood The structure of the hydrated gold(III) tetrachloride salt of l -ecgonine {hydronium tetrakis[(1R,2R,3S,5S,8S)-3-hydroxy-8-methyl-8-azoniabicyclo[3.2.1]octane-2-carboxylate pentakis[tetrachloridoaurate(III)] hexahydrate}, (C9H16NO3)4(H3O)[AuCl4]5·6H2O, demonstrates an unprecedented stoichiometric relationship between the cations and anions in the unit cell. The previous tropane alkaloid structures, including the related hydrochloride salts, all have a cation,anion ratio of 1:1, as does the anhydrous salt described here, namely (1R,2R,3S,5S,8S)-3-hydroxy-8-methyl-8-azoniabicyclo[3.2.1]octane-2-carboxylate tetrachloridoaurate(III), (C9H16NO3)[AuCl4]. The hydrated salt, however, consists of four monopositive N-protonated units of the alkaloid and five [AuCl4], counter-ions, plus seven solvent water molecules. The H atom required for change balance has been assigned to a water molecule. In addition, the hydrate has a novel arrangement, with all seven of the water molecules and all of the O atoms in the cations participating in an alternating arrangement of interleaved sheets of the anionic species. Both the hydrate and the anhydrous salt of the same toxicologically important marker for cocaine show that the cation and anion are in close proximity to each other, as was found in the gold(III) tetrachloride salt of l -cocaine. [source] Two enantiomerically pure cyclic arenesulfonamide hydrochloride saltsACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2009Lionel Kiefer The crystal structures of N -[(1R)-1-(1-naphthyl)ethyl]-3,4-dihydro-2H -1,2-benzothiazin-4-aminium 1,1-dioxide chloride, C20H21N2O2S+·Cl,, (I), a six-membered cyclic sulfonamide, and (1R)- N -[(5,5-dioxo-6,7-dihydrodibenzo[d,f][1,2]thiazepin-7-yl)methyl]-1-(1-naphthyl)ethanaminium chloride, C26H25N2O2S+·Cl,, (II), a seven-membered cyclic sulfonamide, both representative of a novel family of agonists of the extracellular calcium sensing receptor (CaSR) of possible clinical importance, are reported. The known chirality of the naphthylethylamine precursor has enabled assignment of the absolute configuration of both compounds, which is crucial for the receptor recognition. The crystal structures, though different, reveal for these agonists a notable absence of intramolecular ,,, stacking between their respective aromatic groups. This suggests a common structural feature that allows CaSR agonists to be distinguished from antagonists, since in the latter, such interactions have been shown to be important. The connectivities between molecules in the crystal structures are also different, but both involve hydrogen bonding mediated by chloride ions as a common dominant feature. [source] Fluorinated Quinine Alkaloids: Synthesis, X-ray Structure Analysis and Antimalarial Parasite ChemotherapyCHEMISTRY - A EUROPEAN JOURNAL, Issue 31 2009Christoph Bucher Abstract Herein we report the synthesis of a series of C9-fluorinated quinine alkaloids by direct nucleophilic deoxyfluorination. This transformation gives rise to products bearing both S - and R -configured monofluoromethylene functionalities, consistent with an SN1-like mechanism. Furthermore, a series of ring-expanded 1-azabicyclo[3.2.2]nonane systems were generated by a skeletal rearrangement of the quinuclidine core. The modified alkaloids were converted to the corresponding hydrochloride salts and characterised by single-crystal X-ray diffraction analysis. The preference of the benzylic fluorine atom to adopt a gauche conformation relative to the protonated quinuclidine nitrogen atom was consistently observed throughout the cage-conserved compounds. Conversely, the molecular architecture of the 1-azabicyclo[3.2.2]nonane systems enforced an anti relationship between the fluorine atom and the protonated tertiary amine. This constitutes the first X-ray evidence of a vicinal fluorine atom at a stereogenic centre positioned anti to a substituted ammonium cation. The pharmacological efficacy of these compounds was assessed in vitro against the NF54 strain of Plasmodium falciparum (sensitive to all known antimalarial drugs). IC50 values of as low as 267,nM were observed; this highlights the potential of these materials in developing novel agents for parasite chemotherapy. [source] | ||||||||||