Experience with Certified Reference Material Proficiency Testing for Quality Control of Wheat

The Chemical Section of OMH1,2 embarked on the preparation of a series of wheat samples as Certified Reference Materials (CRMs) in 1992. The certification processes were carried out according to the recommendations of ISO. Since then we have developed a series of flour samples as well. The investigations of the long-term stability and the application of wheat and flour CRMs are continuous. Wheat is one of the most widely grown crops in Hungary and it is one of the major determining factors of the economy. Its uniform and objective qualification is of great importance. There are well-equipped laboratories available with sufficient experience but, as the proficiency testing regularly showed, certified samples need to be used to achieve exact and uniform measuring results.

Amin-carbamoyl-10B-boran, Darstellung und biologische Eigenschaften / Amine-carbamoyl-dihydro-10B-borane, Preparation, and Biological Properties

The chemical section deals with the synthesis of sodiumcyano-10B-borhydride (3) from 10B-boric acid trimethyl ester (1) via sodium-10B-borhydride (2). By converting 3 with trimethylammonium chloride, trimethylamine-cyano-10B-borane (4) is formed which, via nitrilium tetrafluoroborate 5, is transformed by water to Trimethylamine-carboxy-dihydro-10B-borane (6). Trimethylamine-ethoxycarbonyl-dihydro-10B-borane (8b) and amine-carbamoyl-dihydro-10B-borane (8c) can be synthesized from the imidazolid 8a. In the biological section an orientation to the toxicity and the tumor affinity of the compounds 6, 7, and 8c are described. Further the possibility is shown by achieving a maximal concentration of 10B-boron in the tumor whilst at the same time retaining as low a concentration of 10B-Boron as possible in the surrounding tissue.

Organic Synthesis and the Unification of Chemistry—A Reappraisal

Proclaiming Louis Pasteur as the “Founder of Stereochemistry”, the distinguished Scottish chemist, Crum Brown, addressing a late nineteenth-century audience of Edinburgh savants, drew attention—as Pasteur had incessantly done—to the intimate relationship between living organisms and the optical activity of compounds sustaining them. It seemed to Crum Brown “that we must go very much further down in the scale of animate existence than Buridan's ass, before we come to a being incapable of giving practical expression to a distinct preference for one of two objects differing only in being one to the right and the other to the left”. Crum Brown's lecture must have been entertaining, but it was also motivated by a serious desire to do justice to a particular assertion of Pasteur—an assertion which had, moreover, been misunderstood and dismissed by no less a chemical genius than Wilhelm Ostwald. Writing at a time when the majority of his colleagues were stressing the resemblances between inorganic and organic compounds, Pasteur had insisted that he “could not point out the existence of any more profound distinction between the products formed under the influence of life and all others” than that “artificial products have … no molecular asymmetry”. Pasteur was obliged to concede that the chemist might produce enantiomorphic pairs of isomers, but without resorting to a manual separation of crystals he was powerless to imitate Nature's performance, powerless to fabricate by chemical means a separate optical isomer, divorced from its partner. Now it was not only Crum Brown who felt that chemists had brushed aside this proposition of Pasteur. In his 1898 Presidential Address to the chemical section of the British Association, Professor F. R. Japp also complained that the possible vitalistic implications of Pasteur's distinction between natural and artificial products had been misapprehended or tacitly ignored.