Sparteine Research Articles

H-bonding binary organocatalysis promoted amine-initiated ring-opening polymerizations of lactide from polysarcosine to diblock copolymers

Alcohol-initiated ring-opening polymerization (ROP) of cyclic esters for synthesizing polyesters was well established, but amine-initiated ROP of cyclic esters was rare. A challenge is slow initiation and fast propagation in the amine-initiated ROPs. To address the difficulties, an ionic H-bond donor (iHBD) and H-bond acceptor (HBA) binary organocatalysis in amine-initiated ROP of lactide (LA) was developed. Guanidinium hexahydro-2H-pyrimido[1,2-a] pyrimidin-1-ium [(HppH2)+] and tertiary amine sparteine (SP), cooperatively played the role of iHBD/HBA binary catalysts, efficiently promoted ROP of LA from amine initiators toward polylactide (PLA) and polysarcosine-block-polylactide diblock copolymer (PSar-b-PLA). Benzyl amine and N-methylbenzylamine initiated ROPs of LA under mild conditions produced PLAs with predictable molecular weights (Mn,NMR = 2.9–17.1 kg mol−1) and narrow dispersities (ÐM,SEC = 1.13–1.23). Macroinitiator PSar copolymerized with LA under the iHBD/HBA catalysis, producing PSar-b-PLAs with controlled molecular weights (Mn,NMR = 5.7–14.8 kg mol−1) and low dispersities (ÐM,SEC = 1.16–1.21). Kinetics and chain extension experiments confirmed that the amine-initiated ROP of LA in presence of (HppH2)+BF4−/SP was in controlled/living manner. 1H NMR, 13C NMR, SEC, and MALDI-ToF MS analyses indicated that the obtained PLA was exclusively initiated from the corresponding amine with amide linkage. An iHBD/HBA binary activation mechanism was proposed.

Chiral Ligand Controlled Helix-sense-selective Atom Transfer Radical Polymerization of 1-Phenyldibenzosuberyl Methacrylate

Abstract The atom transfer radical polymerization (ATRP) of 1-phenyldibenzosuberyl methacrylate was carried out using (−)-sparteine (SP) as ligand. The obtained polymers showed high isotacticity, an excess of right- or left-handed helicity, and were optically active. The control of the stereochemistry might be triggered by the fact that the growing species is complexed with chiral metal complexes and thus the monomer insertion during chain propagation is controlled.

Mass spectrometry characterization of 3‐OH butyrated β‐cyclodextrin

AbstractOligo(3‐OH butyrate)‐β‐cyclodextrin esters (PHB‐CD) were obtained through ring opening of β‐butyrolactone (β‐BL) in the presence of β‐cyclodextrin (CD) and (‐)‐sparteine (SP) as nucleophilic activator. The resulted reaction mixture was first separated in two fractions and then investigated through a deep mass spectrometry (MS) study performed on a liquid chromatography‐electrospray ionization‐quadrupole time of flight (LC‐ESI‐QTOF) instrument. LC MS and tandem MS structural assignment of the reaction products was completed by NMR. The performed analysis revealed that poly(3‐OH butyrate) homopolymers (PHB) are formed together with the PHB‐CD products. Secondary reactions resulting in the formation of crotonates were also proved to occur. A comparison between MS and NMR results demonstrated that more than one PHB oligomer is attached to the CD in the PHB‐CD product. The tandem MS fragmentation studies validated the proposed structure of CD derivatives. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010

(-)-Sparteine mediated α-deprotonation of quinuclidine N-oxide

(-)-Sparteine mediated α-deprotonation of quinuclidine N-oxide

Determination of sparteine in human serum by column-switching HPLC with electrogenerated chemiluminescence detection using tris(2,2'-bipyridine) ruthenium (II)

A sensitive column-switching high-performance liquid chromatography with a tris(2,2'-bipyridine) ruthenium(II) electrogenerated chemiluminescence detection method for the determination of sparteine (SP) in human control serum is described. The procedure is based on the enrichment of SP on column 1, followed by transfer of SP to column 2. Column 1 was a Shim-pack MAYI-ODS (10×4.6 mm, SHIMADZU, Tokyo, Japan). Column 2 was a CAPCELL PACK C18 (150×4.6 mm, SHISEIDO, Tokyo, Japan). The electrogenerated chemiluminescence detector was an ECR COMET-3000KANAGAWA (Comet, Kawasaki, Japan). The mobile phase of column 1 was composed of a 15 mM KH2PO4 buffer at pH 6.0 containing 10 mM octanesulfonate-CH3CN (98:2, v/v) and at a flow rate of 0.5 ml/min. The mobile phase of column 2 was composed of 150 mM KH2PO4 buffer at pH 4.0 containing 10 mM 1-octanesulfonate-CH3CN (73:27, v/v) and at a flow rate of 1.0 ml/min. The reagent solution was 0.3 mM Ru(bpy)32+ in 10 mM H2SO4 and at a flow rate of 0.45 ml/min. The sample in the control serum was directly injected to the HPLC. The linear dynamic range was 125 fmol-2 nmol/ml. The mean recovery for 1 nmol/ml was 98%. The limit of quantitation was 125 fmol/ml and the intermediate precision (CV) was 1.8% (1 nmol/ml, n=5).

Synthesis of Both Enantiomers of Phenylglycine Using (-)-Sparteine

enantioselective deprotonation - (-)-sparteine - carboxylation - silicon rearrangement - phenylglycine

Asymmetric rearrangement of N-Boc 7-azanorbornene oxide: use of aryllithiums for enantioselective deprotonation

The enantioselective α-deprotonation-rearrangement of N-Boc 7-azanorbornene oxide 1 using aryllithiums in the presence of (−)-sparteine 4 or bisoxazolines 5a– c to give azanortricyclanol 2 in up to 87% ee is described.

Sparteine metabolism in Canadian Caucasians.

The capacity for sparteine (SP) metabolism was determined in 48 Caucasian subjects by measuring amounts of drug and dehydrogenated metabolites in urine after an oral dose of SP sulfate. Three phenotypes were recognized and were assumed to represent individuals homozygous for poor SP oxidation (group III) and those heterozygous (group II) and homozygous (group I) for extensive SP oxidation. Separation of groups I and II, although incomplete, was improved by alterations in the published analytic procedure. The pattern of deviations from the normal distribution was similar for both dehydrosparteine metabolites. This supports the hypothesis of a common intermediate, the formation of which is monogenically controlled. Correlation analysis of the two metabolites indicates the possibility of further metabolism of 5-dehydrosparteine.

Segregation of leech neurones by the effect of sparteine on action potential duration.

1. Sparteine (SPT) and 3- or 4-aminopyridine, were applied to leech segmental ganglia and the electrophysiological responses of the Retzius (R) and sensory neurones responding to pressure (P), touch (T), and noxious (N) stimuli analysed. 2. SPT 0.05-0.5 mM when presented via the bath to the whole ganglion prolonged the action potentials of these neurones to characteristically different degrees; the cells were clearly segregated in the order R greater than N greater than P greater than T at 0.5 mM, regardless of exposure time. 3. The plateau of the prolonged action potentials in the R and N cells was sustained by either Ca or Sr and was blocked by Mn, in normal or Na-free Ringer. These responses were similar to those seen in the same cell types with TEA under the same condition. 4. The SPT prolongation of action potentials was favoured by alkalinization of the Ringer solution. This implies that the drug acted in its uncharged form. SPT was ineffective when applied by pressure into the somata of these four neurones. This may be because SPT was charged at the intracellular pH or because it acted at some external membrane site. 5. The aminopyridines when applied in the bath had no effect on the repolarization of these four neurones. 6. These results suggest that TEA and SPT probably act on repolarization by similar mechanisms. The parameter of membrane function principally affected is probably a K current which contributes to repolarization to different degrees in the four cells and which may be activated by Ca.

Analogues of sparteine. II. Synthesis of N-monoalkylbispidines and N,N'-dialkylbispidines.

Analogues of sparteine. II. Synthesis of N-monoalkylbispidines and N,N'-dialkylbispidines.

Analogs of sparteine. I. A reexamination of the reaction of n-methyl-4-piperidone with formaldehyde and methylamine. A revised synthesis of n,n'-dimethylbispidinone.

Analogs of sparteine. I. A reexamination of the reaction of n-methyl-4-piperidone with formaldehyde and methylamine. A revised synthesis of n,n'-dimethylbispidinone.

Alkaloids of the Australian Leguminosae. II. The occurrence of sparteine in Templetonia egena

Alkaloids of the Australian Leguminosae. II. The occurrence of sparteine in Templetonia egena

Piperidylquinolizidines Derived from Sparteine

Piperidylquinolizidines Derived from Sparteine

Toxicity of hydrastine, hydrastinine, and sparteine.

Toxicity of hydrastine, hydrastinine, and sparteine.

A Synthesis of Sparteine and Some Related Substances

The syntheses of sparteine and certain related derivatives of l-azabicyclo-(4,4,0)decane are described and the stereochemistry of sparteine is discussed.

On the synthesis of sparteine and isosparteine

On the synthesis of sparteine and isosparteine

The Numbering of the Sparteine Molecule and its Derivatives

The Numbering of the Sparteine Molecule and its Derivatives

Sparteine at Home

Sparteine at Home