Configuration derivatives

P212121 Z = 4 D = 1.25 R = 0.069 number of intensities not reported. This analysis was to confirm a configuration derived from n.m.r. data. The pyranoid rings are slightly distorted 4Q, due to fusion to the trioxacyclooctane ring, which has an almost ideal, boat-chair conformation. The overall molecule has a convex, sickle conformation. There is an error in the atomic coordinates reported, which do not correspond to the structure given in the paper. 

We now prove (4.33) and show that it is a consequence of the fundamental (4.15) (formulation with configurational derivatives) with the choice... 

The solution using Bethe s method of descending symmetry is summarized in Table 7.8. In the strong-field limit the possible electron configurations derived from d2 in the free ion... 

Non-Newtonian Flow between Jointly Moving Parallel Plates (JMP) Configuration Derive the velocity profile for isothermal Power Law model fluid in JMP configuration. 

This represents a set of p spirals, one on each sublattice v, having respective phases 0 . It is the only configuration derivable from equation 145 that has, to within rotations of the plane of the spins, Sly independent of n. With this equation, the strong constraints of equation 134 become p equations in the p unknowns 0. . . 0P ... 

Pd species. This intermediate undergoes carbonylation, methoxy substitution, and reductive elimination to furnish the Z-configured derivative 193. The resulting Pd(0)-species is reoxidized by oxygen in the presence of iodide ions. On the other hand, the presence of potassium iodide can also equilibrate the ( 2-alkynyl carbamate-Pd-iodide complex to the r/2-alkynyl carbamate-Pd-diiodide complex, which, in turn, causes an anti-attack of the carbamate at the Pdl2-complexed alkyne. Therefore, an antz-vinyl-Pd species results, which ultimately and accordingly leads to the -configured derivative 194. Without carbon monoxide the vinyl-Pd-species suffer a hydro-demetallation. 

The structures of the 9-methyl-5a,9j8,10a-oestran-3-one (1) and its 2a- and 2/8-bromo-derivatives have been studied by X-ray crystallography. Ring A in the 2/8-bromo-compound is forced into a twist-boat conformation by steric compression (2/8-Br/9/3-Me), but the other two compounds are only slightly deformed from the chair conformation. These findings are compatible with the properties (c.d. and n.m.r.) of the same compounds in solution. 3a-Acetoxy-4a,8a,14/8-trimethyl-18-nor-5a,9/3,13a-androstan-17-one (2), another steroid of unusual configuration, derived from fusidic acid, has a twisted boat conformation of ring B. ... 

Since the optical rotations of the D-fructopyranoses differ from those of the D-fructofuranoses in magnitude only (and never in sign), the anomeric configurations of the D-fructofuranoses are established. The /3 configuration derived in this way for the D-fructose moiety in sucrose coincides with the results of previous investigators. ... 

Imines 20 formed from SAMP and enolisable aldehydes prefer an E-configuration across the C=N bond. Lithiation gives the aza-enolate 21 also with the E-configuration derived from the preferred conformation of 20. Reaction with an electrophile gives mostly the diastereoisomer 22. 

In parentheses has been given the absolute configuration derived in this review based on the direction of the optical rotation. Perchlorate. 

The corresponding reductions under catalytic hydrogenation conditions (Pd/C) led exclusively to the yn-configured derivatives (>95 5 syn/anti)P Anri-configured -hydroxy /3-amino esters could be efficiently converted into syn-configured isomers. Reduction of a-amino-y-oxo acids by NaBHa in the presence of a catalytic amount of MnCE (20 mol %) afforded yyn-a-amino-y-hydroxy acids in 60-80% yields and high diastereoselectivities (>95 5 dr) (eq 30).l i ... 

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