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This study evaluated the efficacy and safety of barnidipine for the treatment of mild-to-moderate essential hypertension in Chinese patients. A total of 131 patients were randomized to receive either barnidipine (10-15 mg) or felodipine (5-10 mg) once daily for 4 weeks. Both drugs reduced blood pressure significantly, with ≥ 87% of patients obtaining a marked or moderate effect. The mean ± SD reductions in systolic and diastolic blood pressure were 19.2 ± 13.6 and 14.4 ± 7.0 mmHg, respectively, for barnidipine treatment, and 20.3 ± 11.3 and 14.7 ± 7.7 mmHg, respectively, for felodipine treatment. There were no significant differences between the two drugs in terms of anti-hypertensive effect, heart rate, laboratory test results or incidence of adverse events. More patients taking felodipine experienced palpitations, but this difference was not statistically significant. Barnidipine is as efficacious and safe as felodipine in the treatment of essential hypertension in Chinese patients.

Usually there does not exist an integral invariant of Poincaré-Cartan's type for a nonholonomic system because a constraint submanifold does not admit symplectic structure in general. An integral variant of Poincaré-Cartan's type, depending on the nonholonomy of the constraints and nonconservative forces acting on the system, is derived from D'Alembert-Lagrange principle. For some nonholonomic constrained mechanical systems, there exists an alternative Lagrangian which determines the symplectic structure of a constraint submanifold. The integral invariants can then be constructed for such systems.

The reactions of the mixed-metal metallaborane {Cp*Ru}{Cp*Ru(CO)}{Co(CO)2}(μ-CO)B3H6, 1, Cp* = η⁵-C5Me5, with PPh3 and PMe2Ph as representative phosphine bases and pyridine as a representative nitrogen base have been studied. Phosphines lead to substitution of CO on Co and the formation of {Cp*Ru}2{Co(CO)L}(μ-CO)2B3H4, L = PPh3 (2) and PMe2Ph (3). The latter has been structurally characterized in the solid state and exhibits the fac isomeric form of an octahedral M3B3 cluster. NMR data demonstrate that 3 is fluxional in solution and exists in two isomeric forms:  in the major one the phosphine is adjacent to the B3 face, and in the minor one it is adjacent to the M3 face. Reaction with pyridine leads to three products, two of which have been characterized by X-ray structure determinations. Formation of {(Cp*Ru(CO)}{Co(CO)2}(μ-CO){Cp*Ru}B2H2(NC4H4C), 4, demonstrates borane fragment displacement plus pyridine addition and subsequent orthometalation. Formation of {Cp*Ru}2}{Co(CO)2}(μ-CO)2B2H2B(NC5H5), 5, establishes a parallel pathway involving H substitution on boron accompanied by hydrogen elimination.

Traditionally there do not exist integralinvariants for a nonconservative system in the phasespace of the system. For weak nonconservative systems,whose dynamical equations admit adjoint symmetries, there exist Poincare and Poincare-Cartanintegral invariants on an extended phase space, wherethe set of dynamical equations and their adjointequations are canonical. Moreover, integral invariantsalso exist for pseudoconservative dynamical systemsin the original phase space if the adjoint symmetriessatisfy certain condtions.

Hydrogen loss from the 7 skeletal electron pair (sep) nido 2-Cp*H3WB4H8, 1 (Cp* = η-C5Me5), the metal analogue of pentaborane (9), has been examined as a potential source of unsaturated, reactive species. Pyrolysis of 1 leads to 6 skeletal electron pair (Cp*W)2B5H9, 2 (45%), 7 sep Cp*3W3(μ-H)B8H8 3 (19%), and 7 sep (Cp*W)2B7H9, 4 (low yield), whereas photolysis gives 2 (52%) and 4 (7%). Compound 2 is known, and 3 and 4 have been spectroscopically and crystallographically characterized. Further, the isoelectronic and nearly isostructural analogue of 4, (Cp*Re)2B7H7, 5, has been prepared from the reaction of Cp*ReCl4 and BH3·THF in 66% yield. It is demonstrated that 3 exhibits a skeletal structure corresponding to a highly capped W3 bonded triangle and is analogous to a known multinuclear Ru11 cluster with a hexagonal close packed metal core. As such it constitutes an example of a closed, boron-rich metallaborane cluster with (n − 4) sep. Likewise, it is shown that 4 and 5 possess unusual structures and constitute examples of closed metallaborane clusters with (n − 2) sep. Fenske−Hall MO calculations show that the observed cluster shapes are appropriate for the observed sep's. These two new cluster types demonstrate that transition metal fragments can be used to manipulate the cluster bonding network of a borane, effectively collapsing a single cage into a more closely packed network.

Two new members of human ß-chemokine cDNA were isolated based on structural and functional similarities to human leukotactin-1. One of these clones was identical to the previously isolated human ß-chemokine, CKß8, whereas the other is a splicing variant of CKß8, therefore named CKß8-1. CKß8 was short in 51 nucleotides (17 amino acids) compared with CKß8-1. The mature proteins of CKß8-1 and CKß8 consisted of 116 and 99 amino acids with calculated molecular weights of 12,500 and 10,950, respectively. Both CKß8-1 and CKß8 were potent agonists at CCR1. These chemokines chemoattracted neutrophils, monocytes, and lymphocytes. They also significantly suppressed colony formation by human bone marrow, granulocyte-macrophage, erythroid, and multipotential progenitor cells stimulated by combinations of growth factors. To our knowledge, this is the first example that an alternative splicing produces two active ß-chemokines from a single gene.

The reactions of nido-2,4-(Cp*Co)2B3H7, 1, Cp* = (η⁵-C5Me5), with Fe2(CO)9 and Co2(CO)8 generate seven skeletal electron pair (sep) nido-1-{Cp*Co}-2-((CO)3Fe)B3H7, 2, by metal fragment substitution and seven sep arachno-Cp*(CO)CoB3H7, 3, by metal fragment degradation. Both compounds are characterized spectroscopically in solution and with single-crystal X-ray diffraction in the solid state. On the basis of the results and related chemistry, the suggested reaction pathway involves M(CO)4, M = Fe and Co, coordination to a Co−H−B edge of 1 followed by loss of Cp*Co(CO) which leads to 2. We postulate that the cobalt analogue of 2, which would be an odd-electron species, readily loses a cobalt carbonyl fragment to form 3.

The cluster acid CpM‘(CO)2Co2(CO)6(μ3-CCOOH) (M‘ = Mo, W; Cp = η⁵-C5H5), 1, has been synthesized in good yield from the protected (CO)9Co3(μ3-CC(O)OR) cluster by metal fragment exchange followed by acid hydrolysis. The protonolysis of group 4 M(IV)(OR)4 (M = Zr, Ti) organic alkoxides with this new cluster acid leads to trimetal cluster M(IV) alkoxycarboxylates. The products, which were isolated in good yield as crystalline substances and characterized spectroscopically as well as crystallographically, are Zr2(μ-OH)2{μ-CpMo(CO)2Co2(CO)6(μ3-CCO2)}2{η²-CpMo(CO)2Co2(CO)6(μ3-CCO2)}4, 2; Ti4(μ3-O)4(OR)2)4{μ-CpM‘(CO)2Co2(CO)6(μ3-CCO2)}4, 3 (M‘ = Mo, R = CH(CH2)3, 3a; M‘ = W, R = CH(CH2)3, 3b; M‘ = Mo, R = C2H5, 3c; M‘ = W, R = C2H5, 3d). Direct comparison of this chemistry with that of [(CO)9Co3(μ3-CCO2)]^-, which is of similar size, shows the importance of the electronic properties of the cluster substituent in the metal coordination chemistry of the carboxylate functionality. The exclusive binding of the proximal isomer of the cluster ligand (Cp ring adjacent to the capping carbon) relative to the more stable distal isomer (Cp ring positioned away from the capping carbon) provides definitive evidence for the existence of a cluster electronic effect in the coordination properties of the attached [−CO2]^- group. The significantly different chemistry of cluster vs organic ligands arises in part from this electronic effect.

The protonolysis of group 4 M(IV)(OR)4, M = Ti, Zr, organic alkyl- or aryloxides with the cluster acid (CO)9Co3(μ3-CCO2H) leads to a series of novel tricobalt cluster M(IV) alkoxy- or aryloxycarboxylates, most of which contain bridging oxo ligands. The compounds, which are isolated in good yield as crystalline substances and characterized spectroscopically as well as crystallographically, are Zr2(μ-OCH(CH3)2)2(OCH(CH3)2)2{μ-(CO)9Co3(μ3-CCO2)}2{(CO)9Co3(μ3-CCO2)}2, 1; Ti4(μ3-O)4(OR)4{μ-(CO)9Co3(μ3-CCO2)}4, 2 (R = CH(CH3)2, 2a; (CH2)3CH3, 2b; C6H5, 2c; 2,6-(CH3)2-C6H3, 2d); Ti6(μ3-O)4(μ-OCH2CH3)4(OCH2CH3)8{μ-(CO)9Co3(μ3-CCO2)}4, 3; and [Ti6(μ3-O)2(μ-O)2(μ-OCH(CH3)2)2(OCH(CH3)2)2(1,2-O2C6H4)4{μ-(CO)9Co3(μ3-CCO2)}4], 4. Further, the mixed-metal derivatives [Ti2Co2{(OCH2)3CCH3}2(OCH(CH3)2)2{μ-(CO)9Co3(μ3-CCO2)}4], 5, and [{Co3Ti(OCH3)6(HOCH3)(THF){μ-(CO)9Co3(μ3-CCO2)}3}2(O2CCO2)]·2HOCH3·2THF, 6, in which the Co(II) ions are derived from in situ tricobalt cluster degradation, are characterized in similar fashion. Some of the distinguishing features of an inorganic cluster as a ligand substituent are revealed by a comparison of the observed chemistry with that known for reactions of organic acids with M(IV)(OR)4.

Enantiomerically pure (1R,1‘R)-1,3-bis[1-(diphenylphosphino)ethyl]benzene (4) has been obtained for the first time. The key step involves in situ tosylation of chiral (1S,1‘S)-dimethyl-1,3-benzenedimethanol (6) followed by nucleophilic attack with LiPPh2(BH3) to give [(1R,1‘R)-1,3-bis[1-(diphenylphosphino)ethyl]benzene]−bisborane (7). The bisborane-protected phosphine can be easily handled and purified before deprotecting with HBF4·OMe2 to give the title compound. [(1R,1‘R)-2,6-bis[1-(diphenylphosphino)ethyl]phenyl]chloropalladium(II) (9) and the platinum(II) analogue (8) were synthesized through reaction of the chiral PCP-type ligand with PdCl2(PhCN)2 and [Pt2(μ-Cl)2(η³-CH2C(CH3)CH2)2], respectively, and their X-ray crystal structures were determined. Removal of chloride with AgOTf provided an active catalyst species for the asymmetric aldol reaction of methyl isocyanoacetate and aldehydes.

To analyze the emergence of radiation leukemia virus (RadLV) variants in primary X-ray-induced C57BL/Ka thymoma and to identify the virus responsible for the very high leukemogenic potential of passaged Kaplan strain BL/VL3 preparation, we cloned several primary and passaged ecotropic RadLV infectious genomes. By restriction analysis, we found that BL/VL3 cells harbor three related but different ecotropic RadLVs. Their restriction map differs significantly from those of primary RadLVs. Hybridization analysis also indicated that BL/VL3 and primary RadLVs differ in their p15E and long terminal repeat (LTR) regions. As compared with the LTR sequence of the putative parental endogenous ecotropic provirus, the LTR sequence of primary weakly leukemogenic RadLV has only one change, a C-rich sequence, generating a 6-base-pair direct repeat just in front of the promotor. The LTR of the primary nonleukemogenic RadLV only showed few base changes, mainly clustered in R and U5. The LTR from a moderately leukemogenic passaged BL/VL3 RadLV had conserved the C-rich sequence and acquired a 43-base-pair direct repeat in U3 and several other point mutations, small insertions, and deletions scattered in U3, R, and U5. All cloned primary RadLVs were fibrotropic, and some were weakly leukemogenic. All cloned BL/VL3 RadLVs were thymotropic and nonfibrotropic. The block of their replication was found to be after the synthesis of unintegrated linear and supercoiled viral DNA. Most of the BL/VL3 RadLVs were moderately leukemogenic, and one (V-13) was highly leukemogenic, being as virulent as the Moloney strain. We propose a model for the emergence of the RadLV variants and show that the virus responsible for the high leukemogenic potential of BL/VL3 preparation is a nondefective, ecotropic, lymphotropic, nonfibrotropic, unique retrovirus which most likely arose from a parental primary RadLV similar to those studied here.

We have recently reported that successive treatments of young virgin rats with progesterone (P) implants produce elevated circulating P and consistently low estradiol (E2) concentrations, and subsequently delay the aging-associated reproductive decline. Inasmuch as E2has been implicated in causing the loss of regular estrous cyclicity in aging rats, the present study examined if the concomitant presence of moderately increased circulating E2levels could counteract the effects of P implants on reproductive aging.Starting at 3½ mo and continuing to 8 mo of age, regularly cyclic, virgin rats received either s.c. Silastic implants of P (P-implanted), blank Silastic implants (virgin controls), or P + E2implants (P + E2-implanted) for 3 wk, followed by implant removal for 1 wk. Each of these implant treatments was repeated in the same female rats 5 times. Blood samples were obtained on different days of the estrous cycle from the control group and on Day 11 of successive treatments with P or P + E2implants for measurements of serum P and E2values. At 8½ and 10 mo of age, estrous cyclicity of these same virgin rats was again monitored, and 10-mo-old regularly cyclic females from each treatment group were mated with young fertile males to complete term pregnancies.While virgin controls showed cyclic increases in E2and P secretion during the estrous cycle, P-implanted virgins exhibited consistently low serum E2and moderately increased P levels during 5 successive treatments. The latter indicates a potent inhibition of ovarian E2secretion by P implants. In young females receiving P + E2implants, both serum P and E2levels were consistently higher than those in virgin rats receiving P implants alone. During 8½-l0 mo of age, the incidences of regular estrous cyclicity in female rats of all 3 groups appeared to be inversely related to the overall amounts of circulating E2during the entire period of implant treatments. Thus, at 8½ mo of age, 76% and 55% of virgins that previously received P and P + E2implants maintained regular cyclicity, respectively, whereas only 26% of the virgin controls remained as regularly cyclic. Among the 10-mo-old virgins displaying regular estrous cyclicity, only 20% of the controls became pregnant after mating, whereas 73% and 44% of mated females previously treated with P or P + E2, respectively, were fertile. The litter sizes produced by pregnant rats previously treated with P or P + E2appeared to be greater than those by the control group. These results demonstrate that the effects of P implants to delay reproductive aging in the female rat are partially counteracted, but not abolished, by the concomitant presence of elevated circulating E2. These findings indicate that the amounts of circulating E2rather than P are more influential on the agingassociated reproductive decline.

The thermal conversion of commo-{1-(Cp*Ru)(μ-H)B4H9}2Ru, 1, into {(η⁵-C5Me5)Ru}2{η⁶-C6H6)Ru}B7H7}, 2, is described. Compound 2 is a single cage, hypoelectronic triruthenaborane in which the C6H6 ligand is derived from the reaction solvent. As an (n − 1) skeletal electron pair (sep) closed, deltahedral cluster, 2 constitutes a structural link between 10 fragment metallaboranes with (n + 1) and (n) sep as well as with one with (n − 2) sep. This series establishes a connection between decreasing average coordination number of the cluster boron atoms with decreasing sep thereby providing a useful ¹¹B NMR chemical shift correlation.

Addition of a cobalt carbonyl fragment to (Cp*Ru)3(μ-H)2B3H6 leads to hydrogen loss and formation of the highly condensed (Cp*Ru)3Co(CO)2(μ3-CO)B3H3 cluster. Viewed as a 60-electron tetranuclear metal cluster with six M−M bonds, it completes the series:  64-electron (CpCo)4B4H4 with four M−M bonds; 68-electron (CpNi)4B4H4 with two M−M bonds.

Metal-assisted borane condensation is demonstrated by the formation of the hexaborane(12) analogue arachno-2,5-{Cp*IrH}2B4H8 (3) by the reaction of two BH3·THF moieties with the metal centers of the tetraborane(10) analogue {Cp*IrH}2(μ-H)B2H5 (1). Mild thermolysis of 3, which contains separated B2H4 fragments, results in H2 elimination and the formation of the hexaborane(10) analogue nido-1,2-{Cp*Ir}2(μ-H)B4H7 (2), containing a contiguous B4H7 fragment.

Reaction of either Cp*2Ir2Cl4 or Cp*2Ir2HCl3 with LiBH4 leads to formation of the new iridaborane Cp*Ir(H)2B3H7, 1 (a borallyl complex), in parallel with Cp*IrH4. In contrast, reaction of Cp*2Ir2H2Cl2 with LiBH4 leads exclusively to Cp*2Ir2(H)3B2H5, 3, which is isolobal with 1.

The reaction of (CO)9Co3(μ3-CCOOH) with Ti(OR)4 results in the formation of Ti(IV) oxo alkoxy carboxylates exhibiting new structural forms:  R = Et, Ti6(μ3-O)4(μ-OEt)4(OEt)8{μ-(CO)9Co3(μ3-CCO2)}4 (1); R = Prⁱ, Ti4(μ3-O)4(OPrⁱ)4{μ-(CO)9Co3(μ3-CCO2)}4 (3); R = Ph, Ti4(μ3-O)4(OPh)4{μ-(CO)9Co3(μ3-CCO2)}4 (5); reaction with Ti(OPrⁱ)2(1,2-O2C6H4) yields Ti6(μ3-O)2(μ-O)2(μ-OPrⁱ)2(OPrⁱ)2(O2C6H4)4{μ-(CO)9Co3(μ3-CCO2)}4 (4). Observed stoichiometries and structures reflect the effects of a metal cluster relative to organic substituents.

The reaction of the electronically unsaturated Cp*2Cr2B4H8 (1; Cp* = η⁵-C5Me5) cluster with CS2 yields the saturated Cp*2Cr2(CH2S2B4H6) (3) cluster in better than 90% isolated yield. Both solution spectroscopic and solid-state crystallographic data show that 3, with C2 point symmetry, contains an intracluster bridging methanedithiolato H2CS2 ligand in which the S atoms of the ligand have replaced two transoid BHCr bridging hydrogens in 1, which in turn have added to the carbon atom. The three compounds 1, Cp*2Cr2(CO)2B4H6 (2), and 3 exhibit similar cluster geometries but possess 42, 44, and 46 cluster valence electrons, respectively.

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, is obtained, besides other products, as outlined in the scheme.

The tetranuclear dianion of complex (V) (P1, Z=1) is also prepared by reduction of NbCl3(Ph‐C≡C‐Ph)(THF)2 with Na amalgam and isolated as the dinatrium salt (20% yield, P1, Z=2) with the Na partially coordinated to Cl and THF solvate molecules, and by the same reduction in the presence of PEt3, then isolated as the PHEt3salt (49% yield, P1, Z=1).

By reduction of NbCl5(I) with Bu3SnH (II), followed by addition of diphenylacetylene (III), after suitable workup the crystalline hexaniobium compound (IV) (space group C2/c, Z = 8) is isolated.

The two new compounds, (II) (P21/c, Z = 8) and (VI) (P1, Z=2), obtained by stoichiometric reductions, contain the recently discovered Nb2(PhC)4units.

The ionic compound (II) (space group P21/c, Z=2) is prepared from the monomeric Nb(III) complex (I) by reduction with equimolar amounts of sodium amalgam.