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Lewis-acid catalyzed reactions of unsaturated epoxides 1 and 2 afford the unprecedented products 3 and 5, respectively. Mechanistic pathways for these reactions are presented (Schemes 2 and 4) along with a more fundamental analysis.

A method is described for the rapid and stereoselective assembly of E-trisubstituted olefins by a convergent process from three components

A three-component coupling process is described for the rapid, stereoselective synthesis of a wide variety of E-trisubstituted olefins.

The messenger RNAs present in HeLa cells late in adenovirus 2 infection have been characterized utilizing three complementary methods of analysis. In each case the mRNAs were defined functionally, by identification of the polypeptides they encode when translated in a reticulocyte cell-free system. The RNAs were examined by (1) electrophoretic fractionation in agarose gels containing methyl-mercury hydroxide to estimate the sizes of the functional RNAs; (2) selection by annealing to viral DNA fragments immobilized on nitrocellulose to define the genomic origin of their constituent sequences; (3) hybrid-arrested translation using viral DNA fragments to locate their protein coding sequence. The results allow the positioning of both the coding and non-coding regions of all the late mRNAs with respect to the DNA. They demonstrate that the mature mRNAs originating in the major late transcription unit fall into five families. Within each family the mRNAs overlap in a staggered fashion, sharing the same 3′ terminus but differing at their 5′ termini. The data also reveal the existence of two new late proteins of 52,000 and 55,000 Mr encoded between map co-ordinates 30 to 34 and permit the positioning of the late RNAs, according to the polypeptides they encode, as follows: 52, 55K · IIIa: III · pVII · V: pVI · II: 100 K/33 K · pVIII: IV. (The colons signify the ends of families; centre dots the junctions within families; the slash an overlap of coding sequences; and the comma, coding sequences which have not been separated in this analysis. A 55 K protein has Mr = 55,000.) Those mRNAs which are either the only transcripts from a specific region (such as those for polypeptides IX, IVa2 and IV) or are the 3′-terminal transcripts within a family (such as those coding for polypeptides IIIa, V, II and pVIII) migrate as discrete species upon electrophoresis in agarose gels containing methyl-mercury hydroxide. However, the 5′-proximal RNAs within a family (such as those encoding polypeptides 52, 55 K, III, pVII, pVI, 100 K and 33 K) exhibit a broad distribution of molecular weights.

In a cell-free system derived from wheat germ, the ribonucleic acid of the tobacco mosaic virus mutant Ni 568 directs the synthesis of polypeptides with molecular weights from 10,000 to 140,000, but there is little synthesis of a product equal in size to the coat protein. However, further incubation of the cell-free products with or without extracts from tobacco leaves resulted in the appearance of 35S methionine labeled polypeptides comigrating with tobacco mosaic virus coat protein on sodium dodecyl sulfate-acrylamide gels. Tobacco mosaic virus particles assembled in the presence of these treated cell-free products were shown to be radioactive and co-banded with authentic tobacco mosaic virus during equilibrium centrifugation in cesium chloride. Upon dissociation the assembled particles were found to contain several labeled polypeptides, the most prominent of which comigrated with tobacco mosaic virus coat protein on sodium dodecyl sulfate-acrylamide gels. Furthermore tryptic digests of these polypeptides contained a 35S-methionine labeled peptide with a mobility during high voltage paper ionophoresis at pH 6.5 precisely coincident with that of the only methionine-containing peptide in the coat protein.

Tobacco mosaic virus (TMV) RNA stimulates amino acid incorporation into protein in cell-free extracts from wheat germ, rye embryo and Escherichia coli . The properties of the wheat germ system are examined and the nature of the viral RNA-induced products studied with the aid of a virus mutant carrying a threonine → methionine replacement in its coat protein. A peptide containing this methionine residue is present in tryptic digests of mutant RNA-directed cell-free products, and is absent from digests of wild type RNA-directed products. The undigested cell-free product contains a very large number of polypeptides with molecular weights from 10,000 to 140,000, but little or no synthesis of correct sized coat protein is observed.

Eight cases of lymphoid malignancy preceded by Bell's palsy are reported. There was a disproportionate number of ALL cases, two of which were of T-cell type. The possible pathogenic association of these conditions is discussed.