Ammonium-10-camphorsulfonate

Fig. 2. Tic densitometer scans showing the resolution of isoproterenol on a hpdc silica-gel plate obtained using a mobile phase consisting of 6.8 mM (lR)-(—)-ammonium-10-camphorsulfonic acid in 75 25 (v/v) methylene chloride methanol. (a) 254 nm, (b) 275 m, (c) 300 nm.

Enantiomers of phenylpropanolamine, octopamine, pindolol, norphenyl-ephedrine, propanolol, and isoproterenol were separated with Rf differences of 0.05-0.24 by development of Whatman HP-KF HPTLC plates with dichloro-methane/methanol (75 25) containing different amounts of A-benzoxycarbonyl (BOC)-alanyl-L-proline (ZAP), BOC-isoleucyl-L-proline (ZIP), BOC-L-proline (ZP), BOC-glycyl-L-proline (ZGP), (lR)-(—)-ammonium-10-camphorsulfonate (CSA), and triethylamine (TEA). Visualization was under 254 nm UV light [29]. 

Antipodes of /3-blockers were discriminated using only in one case /3-CD [23] and more often chiral counter-ions such as (lR)-(-)-ammonium-10-camphorsulfonate (CSA), A-carbobenzyloxy-glycyl-L-proline (ZGP), and various... 

Figure 7 shows DRCD spectra taken by our newly developed instrument which has about ten times more light efficiency than the instrument previously made [44]. d- and L-ammonium camphorsulfonate exhibited mirror-image spectra, and these are similar to their respective solution spectra. 

A mixture consisting of aniline ( 0.2 g) and (lS)-(+) camphorsulfonic acid (3.48 g) was dissolved in 10 ml of water and then treated with five separate portions of 0.1 g of ammonium peroxydisulfate dissolved in 1 ml water. Each successive portion was added when the solution turned from blue to green while the reaction mixture was maintained at 20°C. After the additions were completed the mixture was centrifuged and the product washed with water. The circular dichroism spectrum of the product suspensed in water indicated a molar ellipticity of about 90 x 103 deg-cm2/dmol. Transmission electron micrographs showed that the product had a nanofibrous structure with fiber diameters from 30 to 70 nm and had a length of several hundred nanometers. 

Approximately 2ml of aniline was added to 200ml of 1.0M aqueous (lS)-(+) camphorsulfonic acid solution and then treated with ammonium peroxydisulfate (1.15 g) dissolved in 10ml aqueous solution of 1.0M (lS)-(+) camphorsulfonic acid. The solution of ammonium peroxydisulfate was quickly added over several seconds to the solution of aniline and then stirred for 90 minutes. After the reaction was completed, the precipitate was collected and washed with about 400 ml of an aqueous solution of 0.1 M (lS)-(+) camphorsulfonic acid. Washing was repeated until the filtrate was colorless. 

Several different types of chiral additives have been used including (IR)-(-)-ammonium-IO-camphorsulfonic acid, cyclodextrins. proteins, and various amino acid derivatives such as //-benzoxycarbonyl-glycyl-L-proline as well as macrocyclic antibiotics. 

Splitting off the d-camphorsulfonic acid by using ammonium hydroxide and conversion of the desired a-dextro isomer to the hydrochloride only the dextro isomer is active as an analgesic... 

Most CD spectropolarimeters must be calibrated. A common way is to compare the absorption and CD spectra of ammonium (+)-dlO-camphorsulfonate (ACS) using a solntion nominally ImgmL in a 1mm cell. Using the absorption at 285 nm (e28s mn = 34.5 cm ) to determine... 

For organic solvent solubility, an alternative approach to solubilising polyanilines and polypyrroles, without sacrificing high electrical conductivity, is the use of surfactant-like dopant anions. With polypyrrole this has recently been achieved via oxidation of the pyrrole monomer with ammonium persulfate in the presence of dodecylbenzene sulfonate [128,129]. Similarly, the conducting emeraldine salt form of PAn.HA can be readily solubilised in a range of organic solvents via the use of camphorsulfonic acid or dodecylbenzenesulfonic acid as the dopant, HA [130,131]. 

Abbreviations Ac, acetyl AIBN, 2,2 -azobisisobutyronitrile All, allyl Alloc, allyloxycarbonyl Bn, benzyl BOM, benzyloxymethyl BPC, p-phenylbenzoyl Bu, butyl t-Bu, tert-butyl Bz, benzoyl CAN, ammonium hexanitratocerate (IV) Cbz, bezyloxycarbonyl CDl, carbonyldiimizazole ClAc, chloroacetyl Cp, cyclopentadienyl CSA, DL-lO-camphorsulfonic acid DABCO, l,4-diazabicyclo[2.2.2]octane DAST, diethylaminosulfur trifluoride dba, dibenzylideneacetone DBU, l,8-diazabicyclo[5.4.0]undec-7-ene DCC, iV,iV-dicyclohexylcarbodiimide DDQ, 2,3-dichloro-5,6-dicyano-l,4-benzoqui-none DEAD, diethyl azodicarboxylate DEIPS, diethylisopropylsilyl DIBAL, diisobutylaluminum hydride DMAP,... 

Ac AIBN 9-BBN Bn Boc Bu Bz CAN Cbz CD CSA DABCO DAST DBN DBU DCC DDQ DEAD DHP DIAD DIBAL-H DMAP DME DMF DMP DMSO DNB EE Ee Eq Et Fmoc GLC HLADH HMDS HMPA HOBt HPLC Im acetyl 2,2/-azobisisobutyronitrile 9-borabicyclo[3.3.1]nonane benzyl f-butoxycarbonyl butyl benzoyl ceric ammonium nitrate benzyloxycarbonyl circular dichroism camphorsulfonic acid 1.4- diazabicyclo[2.2.2]octane A,A-Diethylaminosulfur trifluoride 1.5- diazabicyclo[4.3.0]non-5-ene l,8-diazabicyclo[5.4.0]undec-7-ene A,A -dicyclohexylcarbodiimide 2.3- dichloro-5,6-dicyano-1,4-benzoquinone diethyl azodicarboxylate 3.4- dihydro-2//-pyrane diisopropyl azodicarboxylate diisobutylaluminum hydride 4-A,A -dimethylaminopyridine 1,2-dimethoxyethane A,A -dimethylformamide Dess -Martin periodinane [1,1,1 -tris(acetyloxy)-1,1 -dihydro-1,2-benziodoxol-3-( IH) -one] dimethyl sulfoxide 3.5- dinitrobenzoyl 2-ethoxyethyl enantiomeric excess molar equivalent ethyl 9-fluorenylmethoxycarbonyl gas-liquid chromatography horse liver alcohol dehydrogenase 1,1,1,3,3,3 -hexamethyldisilazane hexamethylphosphoric triamide 1 -hydroxybenzotriazole high-performance liquid chromatography 1-imidazolyl or imidazole... 

ACS = ammonium (-p)-DlO-camphorsulfonate BSA = bovine serum albumin CD = circular dichroism CT = charge transfer hCCS = human copper chaperone for superoxide dismutase hSCAN = human soluble calcium-activated nucleotidase-1 LMCT = ligand-to-metal charge transfer METP = miniaturized electron transfer protein MLCT = metal-ligand charge transfer ORD = optical rotatory dispersion SODs = superoxide dismutases tCCS = tomato copper chaperone for superoxide dismutase DTP = uracil triphosphate. 

Historically, the azoniaspiroalkanes have been used to settle two controversial points of stereochemistry. There was much discussion of the valency of nitrogen in quaternary ammonium salts, the two views favouring a tetravalent tetrahedral or a pentavalent pyramidal structure. The dispute was settled by the synthesis of compound (11) by Mills and Warren <25JCS2507> which should be resolvable into enantiomers if the nitrogen has tetrahedral valencies, but not with the pyramidal formula (12) which has a plane of symmetry. The compound was resolved as its (< -a-bromo-camphorsulfonate. 

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