Methyl tetra - 0-methyl- ?-D- glucopyranoside is stereoselectively prepared from tetramethyl-D- glucopyranose by using (MeI+NaH) in toluene (86%) or cyclohexane (85%), while its ?- isomer is best synthesized in hexamethyl phosphoramide (64%). Similarly, methyl tetra-o-methyl-?- D-mannopyranoside is synthesized in cyclohexane (80%), while its ?- isomer is predominantly prepared by (MeI+n-Bu...

Hintergrund: Eine Nahrungsmittelunverträglichkeit kann durch einen verminderten enzymatischen Histaminabbau aufgrund einer verringerten Aktivität der Diaminoxidase (DAO) induziert sein (Histaminintoleranz (HIT)). Zielsetzung: Ziel der vorliegenden Studie war es herauszufinden, ob die DAO-Aktivität im Serum bei Patienten, deren Vorgeschichte eine HIT vermuten lässt, im Vergleich zu Patienten ohn...

[reaction: see text] We describe methodology for the in situ generation of reactive monosubstituted ketenes from acid chlorides through a shuttle deprotonation process using NaH as an inexpensive stoichiometric base and a crown ether cocatalyst. We have successfully applied this new procedure to the catalytic, asymmetric synthesis of beta-lactams and alpha-haloesters.

background: acute poisoning has been reported to be the most common reason for hospitalization in iran. this study was designed to delineate the toxic agents responsible for acute poisonings in iran by reviewing poisoning cases treated at four major referral hospitals for treatment of poisoning across the country. methods: this was a descriptive retrospective study on poisoned patients treated ...