76
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Black JD, Stevens ED. Passive stretching does not protect against acute contraction-induced injury in mouse EDL muscle. J Muscle Res Cell Motil 2002; 22:301-10. [PMID: 11808770 DOI: 10.1023/a:1013188001776] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A popular part of many athletes pre-game regime is to stretch. We examined whether a pre-injury stretching protocol could prevent acute contraction-induced injury. The in situ extensor digitorum longus (EDL) muscle of an anesthetized mouse (80 mg/kg intra-peritoneal) was used. Damage to the muscle from eccentric contraction-induced injury was quantified by the deficit in tetanic force production, and was not confounded by metabolic fatigue. The force deficits resulting from eccentric contractions alone (E) were compared with the force deficits resulting from a protocol that consisted of a stretch before the eccentric contractions (S + E). The pre-injury stretch was performed to 5% L0 strain, at a velocity of 0.5 mm/s. The muscle was held in the stretch position for 1 min, then slowly released. Eccentric contraction protocols (excursion > or = 24% L0) resulted in pronounced force deficits that increased with the excursion amplitude of the eccentric contraction. The eccentric contractions also resulted in an average right shift of 2 +/- 0.53% in the length-force relationship (t-test, P = 0.0001). The regression lines for the E (eccentric contraction only) and S + E (stretch and eccentric contractions) treatments did not differ from one another for either force deficit (ANCOVA, P = 0.82) or work deficit (ANCOVA, P = 0.12). Therefore, the pre-injury stretch protocol did not reduce the force deficit or the work deficit resulting from contraction-induced injury.
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77
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Cheng J, Zhang C, Stevens ED, Izenwasser S, Wade D, Chen S, Paul D, Trudell ML. Synthesis and biological evaluation at nicotinic acetylcholine receptors of N-arylalkyl- and N-aryl-7-azabicyclo[2.2.1]heptanes. J Med Chem 2002; 45:3041-7. [PMID: 12086489 DOI: 10.1021/jm0103561] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new series of N-arylalkyl-substituted 7-azabicyclo[2.2.1]heptanes and N-aryl-substituted 7-azabicyclo[2.2.1]heptanes were synthesized and evaluated as potential ligands for neuronal nicotinic acetylcholine receptors. The in vitro binding affinities (K(i)) of the 7-azabicyclo[2.2.1]heptane derivatives were measured by inhibition of [(3)H]cytisine binding to rat brain tissue. The most potent ligand of the series was found to be N-(3-pyridylmethyl)-7-azabicyclo[2.2.1]heptane (5b, K(i) = 98 nM). The chloro analogue (5a, K(i) = 245 nM) 5a and epibatidine (1) produced dose-dependent analgesia in both hotplate and tail-flick tests when administered subcutaneously. However, when compounds 1 and 5a,b were administered intrathecally, all produced analgesia in the tail-flick test but only 5a produced analgesia in the hotplate test.
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MESH Headings
- Analgesics, Non-Narcotic/chemical synthesis
- Analgesics, Non-Narcotic/chemistry
- Analgesics, Non-Narcotic/pharmacology
- Animals
- Body Temperature/drug effects
- Brain/metabolism
- Bridged Bicyclo Compounds, Heterocyclic/chemical synthesis
- Bridged Bicyclo Compounds, Heterocyclic/chemistry
- Bridged Bicyclo Compounds, Heterocyclic/pharmacology
- Crystallography, X-Ray
- Dopamine/metabolism
- In Vitro Techniques
- Injections, Spinal
- Ligands
- Mice
- Nicotinic Agonists/chemical synthesis
- Nicotinic Agonists/chemistry
- Nicotinic Agonists/pharmacology
- Pain Measurement
- Pyridines/chemistry
- Pyridines/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptors, Nicotinic/metabolism
- Structure-Activity Relationship
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78
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Viciu MS, Kissling RM, Stevens ED, Nolan SP. An air-stable palladium/N-heterocyclic carbene complex and its reactivity in aryl amination. Org Lett 2002; 4:2229-31. [PMID: 12074674 DOI: 10.1021/ol0260831] [Citation(s) in RCA: 212] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] The synthesis and characterization of [Pd(IPr)Cl(2)](2) (1), an air- and moisture-stable complex, is reported. The utilization of 1 as a catalyst for amination of aryl chlorides and bromides with a variety of amine coupling partners under mild conditions is described. The amination reactions with 1 show a remarkable insensitivity to oxygen and water, and thus the amination reactions could be performed in air on the benchtop with undried reagent grade solvents and substrates with small effects on reaction times and conversions.
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79
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Klein CL, Majeste RJ, Luedtke AE, Ray WJ, Stevens ED, Timberlake JW. Synthesis and crystallography of 2,3,3,5,6,6-hexamethyl-3,6-dihydropyrazine hexahydrate and 3-amino-3-methyl-2-butanone hydrochloride. J Org Chem 2002. [DOI: 10.1021/jo00181a013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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80
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Syed A, Stevens ED, Cruz SG. Reexamination of the .pi. bonding in dichloro(cycloocta-1,5-diene)platinum. Inorg Chem 2002. [DOI: 10.1021/ic00190a053] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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81
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Liang L, Stevens ED, Nolan SP. Synthesis and characterization of an organoyttrium dimer produced via an Arbuzov dealkylation reaction. Organometallics 2002. [DOI: 10.1021/om00046a055] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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82
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Bachman DF, Stevens ED, Lane TA, Yoke JT. Methanolysis of tetrakis(phosphorus trichloride)nickel(0). Inorg Chem 2002. [DOI: 10.1021/ic50107a025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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83
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Lecomte C, Chadwick DL, Coppens P, Stevens ED. Electronic structure of metalloporphyrins. 2. Experimental electron density distribution of (meso-tetraphenylporphinato)iron(III) methoxide. Inorg Chem 2002. [DOI: 10.1021/ic00163a003] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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84
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Li C, Stevens ED, Nolan SP. Solution Thermochemical Study of Ligand Steric Influences on Substitution Enthalpies in the L2Fe(CO)3 System. Organometallics 2002. [DOI: 10.1021/om00008a028] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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85
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Nolan SP, Martin KL, Stevens ED, Fagan PJ. Enthalpies of reaction of ruthenium complex Cp*Ru(CH3CN)3+O3SCF3- (Cp* = .eta.5-C5Me5) with arenes. Solution thermochemical study of arene binding to the Cp*Ru+ fragment. Organometallics 2002. [DOI: 10.1021/om00060a008] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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86
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Birdwhistell TLT, Stevens ED, O'Connor CJ. Synthesis and crystal structure of a novel layered Zintl phase: potassium gallium arsenide (K3Ga3As4). Inorg Chem 2002. [DOI: 10.1021/ic00344a047] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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87
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O'Connor CJ, Firmin D, Pant AK, Babu BR, Stevens ED. Binuclear molecules incorporating small molecules as bridging ligands. Magnetic properties and molecular structure of [Cu2L(B)]2+ where B = hydroxide or bromide and HL = 2,6-bis(N-(2-pyridylmethyl)formimidoyl)-4-methylphenol. Inorg Chem 2002. [DOI: 10.1021/ic00234a005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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88
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Subramanian G, Boyer JH, Buzatu D, Stevens ED, Trudell ML. Reactions of Benzotriazolo[2,1-a]benzotriazole Derivatives. 1. Synthesis of New Insensitive High-Density Energetic Compounds. J Org Chem 2002. [DOI: 10.1021/jo00124a024] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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89
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Wang KG, Stevens ED, Nolan SP. Synthesis and structural characterization of a tetranuclear organolanthanide hydrazido complex. Organometallics 2002. [DOI: 10.1021/om00039a003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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90
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Mague JT, Klein CL, Majeste RJ, Stevens ED. Synthesis of binuclear cationic complexes of iridium containing a dimetalated olefin and the crystal and molecular structures of [Ir2(CO)3Cl(.mu.-H3CO2CC:CCO2CH3)((C6H5)2PCH2P(C6H5)2)2]PF6.CH3CN. Organometallics 2002. [DOI: 10.1021/om00090a014] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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91
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Serron SA, Luo L, Li C, Cucullu ME, Stevens ED, Nolan SP. Enthalpies of Reaction of Cp'Ru(COD)Cl (Cp' = C5H5, C5Me5; COD = Cyclooctadiene) with P(p-XC6H4)3 (X = Cl, F, H, CH3, CF3, OCH3) Ligands: Ligand Steric vs Electronic Contributions to the Enthalpy of Reaction. Organometallics 2002. [DOI: 10.1021/om00011a053] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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92
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Coppens P, Holladay A, Stevens ED. Agreement between transition-metal orbital populations from x-ray and polarized neutron-scattering experiments. J Am Chem Soc 2002. [DOI: 10.1021/ja00376a070] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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93
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Stevens ED, Kramer JD, Paquette LA. X-ray crystal structure analysis of triquinacene at 90 K. J Org Chem 2002. [DOI: 10.1021/jo00875a010] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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94
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Timberlake JW, Ray WJ, Stevens ED, Klein CL. Synthesis of 1,2,5-thiadiazolidin-3-one 1,1-dioxides: x-ray structure determination of 4,4-diphenyl-1,2,5-thiadiazolidin-3-one 1,1-dioxide. J Org Chem 2002. [DOI: 10.1021/jo00285a035] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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95
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Li C, Cucullu ME, McIntyre RA, Stevens ED, Nolan SP. Enthalpies of Reaction of CpRu(COD)Cl (Cp = .eta.5-C5H5; COD = Cyclooctadiene) with Chelating Tertiary Phosphine Ligands. Solution Thermochemical Investigation of Ligand Substitution and Ring Strain Energies in CpRu(R2P(CH2)nPR2)Cl Complexes. Organometallics 2002. [DOI: 10.1021/om00021a039] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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96
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Klein CL, Majeste RJ, Stevens ED. Experimental electron density distribution of naloxone hydrochloride dihydrate, a potent opiate antagonist. J Am Chem Soc 2002. [DOI: 10.1021/ja00256a021] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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97
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Stevens ED. Electronic structure of metalloporphyrins. 1. Experimental electron density distribution of (meso-tetraphenylporphinato)cobalt(II). J Am Chem Soc 2002. [DOI: 10.1021/ja00407a023] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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98
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Luo L, Zhu N, Zhu NJ, Stevens ED, Nolan SP. Enthalpies of reaction of ruthenium complex Cp*Ru(COD)Cl (Cp* = .eta.5-C5Me5; COD = cyclooctadiene) with chelating tertiary phosphine ligands. Solution thermochemical investigation of ligand substitution and ring strain energies in Cp*Ru(PP)Cl complexes. Organometallics 2002. [DOI: 10.1021/om00014a044] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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99
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Peralta-Inga Z, Johnson GP, Dowd MK, Rendleman JA, Stevens ED, French AD. The crystal structure of the alpha-cellobiose.2 NaI.2 H(2)O complex in the context of related structures and conformational analysis. Carbohydr Res 2002; 337:851-61. [PMID: 11996839 DOI: 10.1016/s0008-6215(02)00041-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The crystal structure of beta-D-glucopyranosyl-(1-->4)-alpha-D-glucopyranose (alpha-cellobiose) in a complex with water and NaI was determined with Mo K(alpha) radiation at 150 K to R=0.027. The space group is P2(1) and unit cell dimensions are a=9.0188, b=12.2536, c=10.9016 A, beta=97.162 degrees. There are no direct hydrogen bonds among cellobiose molecules, and the usual intramolecular hydrogen bond between O-3 and O-5' is replaced by a bridge involving Na+, O-3, O-5', and O-6'. Both Na+ have sixfold coordination. One I(-) accepts six donor hydroxyl groups and three C-H***I(-) hydrogen bonds. The other accepts three hydroxyls, one Na+, and five C-H***I(-) hydrogen bonds. Linkage torsion angles phi(O-5) and psi(C-5) are -73.6 and -105.3 degrees, respectively (phi(H)=47.1 degrees and psi(H)=14.6 degrees ), probably induced by the Na+ bridge. This conformation is in a separate cluster in phi,psi space from most similar linkages. Both C-6-O-H and C-6'-O-H are gg, while the C-6'-O-H groups from molecules not in the cluster have gt conformations. Hybrid molecular mechanics/quantum mechanics calculations show <1.2 kcal/mol strain for any of the small-molecule structures. Extrapolation of the NaI cellobiose geometry to a cellulose molecule gives a left-handed helix with 2.9 residues per turn. The energy map and small-molecule crystal structures imply that cellulose helices having 2.5 and 3.0 residues per turn are left-handed.
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100
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Jursic BS, Neumann DM, Moore Z, Stevens ED. Unique charge-separated pyridinium-barbituric acid zwitterions. J Org Chem 2002; 67:2372-4. [PMID: 11925259 DOI: 10.1021/jo0161431] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A synthetic procedure for the preparation of the unusual charge-separated pyridinium barbiturate zwitterion 2 from 1,3-dimethylbarbituric acid and 2-pyridinecarbaldehyde in methanol was developed. The structure of the compound was confirmed with X-ray analysis to demonstrate the strong charge separation throughout the molecule. One would expect that this charge separation would increase its reactivity; however, contrary to this expectation, the compound is very stable in acidic media, and in the presence of a base, decarbonylation occurs on one barbituric acid while the zwitterionic moiety of the molecule stays intact.
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