'Chiral methyl valines', i.e. samples of valine labelled stereospecifically in the methyl groups with 2H and 3H, were incorporated into cephalosporin C by a suspension of washed cells of Cephalosporium acremonium. Analysis by 3H n.m.r. of the cephalosporin C produced showed that the conversion of the 3-pro-S-methyl group of valine into the acetoxymethyl side-chain was a highly stereospecific process. By contrast, conversion of the 3-pro-R-methyl group into the endocyclic methylene group of the dihydrothiazine ring was shown to proceed by a non-stereospecific process.

Abstract-Poststroke motor control is characterized by greatly reduced muscle power generation. To date, the extent to which muscle power limits walking performance or whether its remediation should be a primary component of locomotor rehabilitation has yet to be established. The purpose of this study was to examine the feasibility and the effects of Poststroke Optimization of Walking using Explosive Resistance training, an intervention aimed at improving poststroke muscular and locomotor function. Twelve subjects (6-60 mo poststroke) participated in 24 training sessions (3 sessions/wk for 8 wk). Exercises included leg press, calf raises, and jump training, all performed at high concentric velocity, as well as trials of fast walking. We measured selfselected and fastest comfortable walking speeds as well as knee extensor and plantar flexor strength and power at pretraining, posttraining, and 8 wk follow-up time points. In addition, we also performed a number of clinical assessments commonly used in poststroke rehabilitation trials. Following training, significant improvements in lower-limb muscle strength and power were realized and accompanied by improvements in self-selected as well as fastest comfortable walking speeds. No changes in clinical assessments resulted from training.

On treatment with silver­(I) oxide the complex [Cp*RhCl2(κC-MeNC3H2NCH2C6F5)] undergoes 1,4-addition of rhodium and methylene to the polyfluoroaryl ring, which loses aromaticity, affording [(η5,κ2 C-C5Me4CH2C6F5CH2NC3H2NMe)­RhCl].

We report a fluorine transfer reaction in which fluorine from a perfluorinated ligand undergoes C−F bond activation and transfers to an electrophile, resulting in the formation of a new fluorinated product and dimerization of the monodefluorinated complex. Treatment of [(η 5 ,κ 2 C− C 5 Me 4 CH 2 C 6 F 5 CH 2 NC 3 H 2 NMe)−RhCl] with the organic electrophile, toluoyl chloride, resulted in the formation of a rhodium(III) metallocycle via C−F bond activation assisted defluorinative coupling. Fission of the C− F bond liberated nucleophilic fluoride, which converted acyl chloride to acyl fluoride. The overall reaction was monitored using a multivariate analysis approach in real time.

These data demonstrate that lower extremity strength is associated with walking ability after iSCI. Correlations for the muscle groups of the move-involved side were stronger compared to the less-involved limb. In addition, PF function is highlighted as a potential limiting factor to walking speed along with the importance of RTD.