Synthèses stéréosélectives de composés organostanniques diastéréoisomères du type S-CHD-CHD-SnR3

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Synthesis of Highly Enantioenriched Chiral alpha-Aminoorganotins via Diastereoselective Ring Opening of Chiral N-(Arenesulfonyl) 2-Tributylstannyloxazolidines

International audiencetrans-N-(Arenesulfonyl)-2-tributylstannyloxazolidines derived from (R)-phenylglycinol were diaster-ecoselectively ring-opened by soft organometallic reagents in the presence of BF3 center dot OEt2. Both higher order organocuprates and allyltributyltin afforded the desired products in good-to-excellent yields and high diasterecoseloctivities (dr tip to 99/1). The stercochemical assignments of tributylstannyl-beta-aminoalcohols were firmly established from NMR data and after determination of several radiocrystallographic structures. Mechanisms were proposed in order to rationalize the observed selectivities

Hypertonic Lactate to Improve Cerebral Perfusion and Glucose Availability After Acute Brain Injury.

Lactate promotes cerebral blood flow and is an efficient substrate for the brain, particularly at times of glucose shortage. Hypertonic lactate is neuroprotective after experimental brain injury; however, human data are limited. Prospective study (clinicaltrials.gov NCT01573507). Academic ICU. Twenty-three brain-injured subjects (13 traumatic brain injury/10 subarachnoid hemorrhage; median age, 59 yr [41-65 yr]; median Glasgow Coma Scale, 6 [3-7]). Three-hour IV infusion of hypertonic lactate (sodium lactate, 1,000 mmol/L; concentration, 30 µmol/kg/min) administered 39 hours (26-49 hr) from injury. We examined the effect of hypertonic lactate on cerebral perfusion (using transcranial Doppler) and brain energy metabolism (using cerebral microdialysis). The majority of subjects (13/23 = 57%) had reduced brain glucose availability (baseline pretreatment cerebral microdialysis glucose, < 1 mmol/L) despite normal baseline intracranial pressure (10 [7-15] mm Hg). Hypertonic lactate was associated with increased cerebral microdialysis lactate (+55% [31-80%]) that was paralleled by an increase in middle cerebral artery mean cerebral blood flow velocities (+36% [21-66%]) and a decrease in pulsatility index (-21% [13-26%]; all p < 0.001). Cerebral microdialysis glucose increased above normal range during hypertonic lactate (+42% [30-78%]; p < 0.05); reduced brain glucose availability correlated with a greater improvement of cerebral microdialysis glucose (Spearman r = -0.53; p = 0.009). No significant changes in cerebral perfusion pressure, mean arterial pressure, systemic carbon dioxide, and blood glucose were observed during hypertonic lactate (all p > 0.1). This is the first clinical demonstration that hypertonic lactate resuscitation improves both cerebral perfusion and brain glucose availability after brain injury. These cerebral vascular and metabolic effects appeared related to brain lactate supplementation rather than to systemic effects

Antifungal therapy for patients with proven or suspected Candida peritonitis: Amarcand2, a prospective cohort study in French intensive care units

International audienc