Heteropolyacid-Catalyzed Phosphorylation of Secondary Aromatic Alcohols with H-Phosphine Oxides in DMC: A Simple Protocol for C-P Bond Formation.

We successfully achieved the phosphorylation of secondary aromatic alcohols with H-phosphine oxides (less developed system) using phosphotungstic acid as a catalyst in dimethyl carbonate. The system was simple and environmentally friendly and showed better activity than traditional Lewis or Brønsted acids such as FeCl3, p-TsOH·H2O, etc., generating up to a 97% isolated yield. Control experiments indicated that the reaction did not occur through the radical pathway, and ethers and carbocation were the key intermediates in the pathway.

Direct deoxygenation of active allylic alcohols via metal-free catalysis.

Direct metal-free deoxygenation of highly active allylic alcohols catalyzed by a Brønsted acid was achieved, which avoids tedious reaction steps and eliminates metal contamination. By examining a series of Brønsted acids, alcohols, reaction temperatures and so on, up to 94% yield was obtained with 10 mol% TsOH·H2O as the catalyst and 2 equiv. of p-methylbenzyl alcohol as the reductant at 80 °C for 2 h. The system was mainly suitable for aromatic allylic alcohols, and the yield was excellent as determined via gram-scale synthesis. The main product was double bond near the side of a more electron-rich aryl group when allylic alcohols featuring different substituents at the 1 and 3 positions were used as the substrates. Deuterium-labelled experiments clearly demonstrated that the hydrogen source was the methylene of p-methylbenzyl alcohol and other control experiments indicated the existence of two ether intermediates. Interestingly, in situ hydrogen transfer of allylic benzyl ether is a key process, but kinetic isotopic effect studies (kH/kD = 1.28) showed that the C-H bond cleavage was not the rate-determining step. A possible mechanism involving carbocations, ether intermediates and hydrogen transfer is proposed.

Amniotic stem cell transplantation therapy for type 1 diabetes: a case report.

This case report presents an evaluation of the clinical effects of an allogeneic amniotic cell transplant for the treatment of type 1 diabetes mellitus. A 26-year-old man with type 1 diabetes was treated with stem cells isolated from his neonatal son's amniotic membrane, collected at birth (2 × 10(7) cells). The cells, which expressed high levels of cluster of differentiation (CD) 133 and CD34 as assessed by flow cytometry, were infused into the pancreatic dorsal artery through the left femoral artery. The main study outcome was the change in exogenous insulin requirements, which began to decrease 3 days after transplantation. At 3 months post-transplantation, the patient was insulin independent and remained so for 6.2 months. During a 36-month follow-up, the patient's blood glucose remained under control and insulin treatment was readjusted to a dosage of 8 IU/day. These preliminary data suggest that amniotic membrane stem cell transplantation can improve islet-cell function in response to glucose in vivo, although an alternative explanation (such as a honeymoon period due to reduced glucose toxicity) also has to be considered.