No abstract

No abstract

South Parks Road, Oxford OX1 3QYStructural investigation of the products obtained by microbiological hydroxylation of substrates in the androstane, pregnane, and mstrane series has involved examining the l H n.m.r. spectra of 344 steroids, 243 of them being new compounds. Mild oxidation of the products gives polyketones in which the positions of the oxo-groups are characterised by the chemical and solvent shifts of the 18-H and 19-H signals. This information is supplemented by the chemical shifts of the products' 18-H and 19-H signals, and by the positions and form of their )CH-OH resonances : the latter are especially useful in establishing the configurations of the hydroxy-groups.FOR the past five years we have been studying the hydroxylation of mono-and di-oxygenated steroids with a range of micro-0rganisrns.l The intention was to vary the positions of the oxygen substituents around the steroid nucleus in a systematic manner: it was -gate, ibid., 1969, 463. hoped that the use of relatively simple substrates would facilitate interpret at ion of the microbiological behaviour. A considerable body of results has accrued from examining monoketones, keto-alcohols, and diketones derived from handrostane, 5a-pregnane, and 5a-cestrane ; a series of papers describing the work will be submitted shortly to this Journal. The preparation of substrates and related chemical studies are being recorded in a separate series2

The synthesis of a series of diphenylpoly-ynes Ph*[CiC];Ph is described, those with n = 3, 4, 6, and 8 having been isolated and crystallised. Their ultra-violet and infra-red spectra are described and discussed, and compared with those of the corresponding polyenes.THE diphenylpolyenes (11) are much more stable than the purely aliphatic polyenes.Consequently, having prepared a number of aliphatic conjugated polyacetylenes (Cook, Jones, and Whiting, J., 1952, 2883) which on the whole proved to be rather unstable, we turned to the synthesis of the presumably more stable diphenylpoly-ynes (I). Such a project appeared additionally attractive since it offered the possibility of comparisons with the well-known diphenylpolyenes, synthesised and studied by Kuhn and his collaborators (for summary see J., 1938, 605).Four new members of the series (I), where n = 3, 4, 6, and 8, have been obtained, and the general laws defining their spectrographic properties elucidated. After the completion of most of this work, independent syntheses of (I; n = 3 and 4) (Nakagawa et aZ., Chem.

No abstract