Glycosylation of cardenolides. VIII. Structures of the by-products of the synthesis by the orthoester method of strophanthidol rhamnosides
The by-products formed in the preparation of strophanthiodol 19-rhamnoside and 3, 19-bisrhamnoside by the orthoester method are 3β,5-dihydroxy-8,19-epoxy-5β,14β, 17α-card-20(22)-enolide and its 3-α-L-rhamnoside. 3β,5-Dihydroxy-8,19-epoxy-5β, 14α,17β-card-20(22)-enolide has been obtained by the action of a solution of HBr in nitromethane on strophanthidol.
Untersuchungen über Steroide XLII. Umwandlung des 17α‐Pseudostrophanthidins in 19‐Hydroxy‐8, 19‐epoxy‐14β, 17α‐cortexon und 8‐Hydroxy‐19‐nor‐14β, 17α‐cortexon
The synthesis of a structural isomer of aldosterone, viz. 19-hydroxy-8, 19-epoxy-(11-) de(s)oxycorticosterone (= 19-hydroxy-8, 19-epoxy-cortexone), and a number of related compounds was reported earlier from this laboratory [1]. It appeared desirable to prepare the corresponding compounds of the 17α-series also, such as 19-hydroxy-8, 19-epoxy-14 β, 17 (βH)-deoxycorticosterone (28). 17 α-Pseudostrophanthidin (2), which has not yet been described in the literature, was considered as starting material for the synthesis of 28. 2 has now been prepared by heating a solution of pseudostrophanthidin (1) in dimethylformamide in the presence of sodium p-toluenesulfonate and anhydrous sodium acetate. 2 was characterized as the 3, 19-diacetate (7), the 19-methylal (8) and the 3-monoacetat (9). 9 was also obtained by acetylating the methylal 8 and demethylating the resulting reaction product 10. To support the structures assigned to 9 and, by implication, to 2, a series of further reactions were carried out.
A numerical study on liquid ring motion and fragmentation for the initial process of liquid explosive dispersal
For the explosive dispersal on liquid fuel of FAE technique, the expansion of gaseous detonation products, axisymmetric radial extension and fragmentation of a liquid ring were analyzed, then corresponding models were established. By those models coupled, the numerical simulation on motion and fragmentation of the liquid ring exerted by strong action was carried out. The results computed show that the models established are feasible, and present study can offer initial conditions for the numerical simulation on the process of liquid secondary breakup and gas-liquid mixing.