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Suffixes can be combined, as in methylidyne (triple bond) vs. methylylidene (single bond and double bond) vs. methanetriyl (three double bonds). There are some retained names, such as methylene for methanediyl, 1,x- phenylene for phenyl-1,x-diyl (where x is 2, 3, or 4), [ 5 ] carbyne for methylidyne, and trityl for triphenylmethyl.
Bifurcated H-bond systems are common in alpha-helical transmembrane proteins between the backbone amide C=O of residue i as the H-bond acceptor and two H-bond donors from residue i + 4: the backbone amide N−H and a side-chain hydroxyl or thiol H +. The energy preference of the bifurcated H-bond hydroxyl or thiol system is -3.4 kcal/mol or -2. ...
In contrast to NH 3, NF 3 has a much lower dipole moment of 0.234 D. Fluorine is more electronegative than nitrogen and the polarity of the N-F bonds is opposite to that of the N-H bonds in ammonia, so that the dipole due to the lone pair opposes the N-F bond dipoles, resulting in a low molecular dipole moment. [6]
The general formula is R−SO 2 NR'R" or R−S(=O) 2 −NR'R", where each R is some organic group; for example, "methanesulfonamide" (where R = methane, R' = R" = hydrogen) is CH 3 SO 2 NH 2. Any sulfonamide can be considered as derived from a sulfonic acid by replacing a hydroxyl group ( −OH ) with an amine group.
The thiourea hydrogen bonds to the nitro group and stabilizes the incoming negative charge, while the amine acts a specific base to activate the nucleophile. This is an example of bifunctional catalysis. Hydrogen-bond catalysis is a type of organocatalysis that relies on use of hydrogen bonding interactions to accelerate and control organic ...
The [W(PR 3) 2 (CO) 3 (H 2)] complex was the first well characterized example of both a non-classical dihydride and sigma-bond complex in general. [ 16 ] [ 17 ] X-ray diffraction is generally insufficient to locate hydrides in crystal structures and thus their location must be assumed.
Examples include Captan, which is considered carcinogenic under some conditions, and Procymidone. [ 4 ] Illustrative imides, from left: N -ethylmaleimide , a biochemical reagent; phthalimide , an industrial chemical intermediate; Captan , a controversial pesticide; thalidomide , a drug that once caused many birth defects; a subunit of Kapton ...
As an example, consider the cyclic group Z 12 with generator u, which has two minimal normal subgroups, one generated by u 4 (which gives a normal subgroup with 3 elements) and the other by u 6 (which gives a normal subgroup with 2 elements). Thus the socle of Z 12 is the group generated by u 4 and u 6, which is just the group generated by u 2.