A table providing the energy values of1,3-diaxial interactions of a variety of substituents with a single hydrogen atom is provided below. A gauche interaction increases the strain in the molecule by3.8kJ/mol.Calculate the strain in the most ...
They allow 1,2-diaxial eliminations of HBr leading to PBCDens 5b and 3a, when starting with (+)β- and (−)β-HBCD (A,B). PBCDen 8b is the expected product for both ε-HBCD-enzyme complexes (C,D). 4. Conclusions The large-scale application of HCHs as insecticides, until the ...
positions and orientations relative to the substrate suggest that the enzyme likely imposes an unfavorable constraint on the native substrate IGA. Here, aromatization alters the pseudodiaxial conformation, elongating the C3-O distance, placing strain on the IGA substrate to break the C-O bond, and...
A two-step mechanism has been proposed that indicates that the catalytic process proceeds via trans-diaxial elimination of the 1α,2β hydrogen atoms from a 3-ketosteroid substrate [30]. Interaction of the C3 carbonyl group of a steroidal substrate with an electrophile promotes labilization of ...
the observed NOE correlation from the proton of 10-OH to H-11 established the trans-diaxial orientation of H-10 and H-11, whereas the observed NOE correlations from Ha-5 to H-11 and H3-22 and from H3-22 to H3-23 placed these groups on the same side of the molecule (Figure 3)....
the observed NOE correlation from the proton of 10-OH to H-11 established the trans-diaxial orientation of H-10 and H-11, whereas the observed NOE correlations from Ha-5 to H-11 and H3-22 and from H3-22 to H3-23 placed these groups on the same side of the molecule (Figure 3)....