A variety of diethyl 1-substituted vinylphosphonates has been conveniently synthesized by piperidine catalyzed decarboxylative condensation of 2-diethoxyphosphorylalkanoic acids and 2-dietoxyphosphorylalkenoic acids with formaldehyde.
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Opracowano warunki inwersji konfiguracji trzeciorzędowej grupy hydroksylowej w syntonie pierścieni AB idarubicynonu.
EN
Waste 3-acetyl-5,8-dimetoxy-3-hydroxy-3,4-dihydro-2Hnaphthalene-1-spiro-2’-1’-3’-dithiolane 4, a 7:3 mixture of (R) and (S) enantiomers on boiling with ethyl acetate afforded hydroxyketone (R)-4 with high enantiomeric purity (ca. 96%). A two-step inversion of the stereogenic center in the latter gave hydroxyketone (S)-4 in 40% yield. The overall yield of (S)-4, an advanced intermediate in the synthesis of idarubicinone, was thus raised by about 10%.
Structure - activity relationship studies on oxime phosphates against Musca domestica L., Blatta orientalis L., Leptinotarsa decemlineata Say, Sithophilus granarius L., Acyrthosiphon pisum Harris, Tetranychus urticae Koch, were discussed. The compounds studied revealed very slight insecticidal activity in respect to the known and applied zoocides. Some regularity between structure and activity, mainly in comparison with the corresponding enolphosphates, was observed. The highest activity of the compounds with ethoxy groups at the phosphorus atom was shown and the poorest activity was observed for the compounds containing n-propyl groups at this atom. In contrast to enolphosphates the oxime phosphates with methoxy groups at phosphorus atom exhibit particularly poor activity.
Results of studies on entitled compounds activity against Musca domestica L., Blatta orientalis L., Tetranychus urticae Koch, are presented. These compounds have low insecticidal and acaricidal activity. The relationship between their chemical structure and activity was also investigated.
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