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Then make the entire top surface of plate to chemical treatment by making to flatten wooden board again to mechanical treatment for the manufacturing method with historical relics or the timber floor plate seen used
Then make the entire top surface of plate to chemical treatment by making to flatten wooden board again to mechanical treatment for the manufacturing method with historical relics or the timber floor plate seen used
Hydrogenation of the exocyclic methylene gp. of a 6-deoxy-6-demethyl-6-methylene-tetracycline (I), or its acid addition salt, in a stereoselective manner giving the alpha-isomer in preference to the beta-isomer, is carried out at 20-100 degrees C and 1-100 atmos. under neutral conditions, or using a weakly acidic acid addn. salt, in the presence of a catalytic amt. of a cpd. of formula Rh(OCOR)2(P C6H5 3) (II) (where R = H, 1-6C alkyl, ClCH2, Cl2CH, Cl3C, FCH2, F2CH, F3C, phenyl, chlorphenyl, tolyl, anisyl). The ratio of alpha-isomer to beta-isomer is =9:1. Known methods give a less favourable ratio e.g. 1:1.
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