Gene/Protein
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Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
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Target Concepts:
Gene/Protein
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Query: UNIPROT:P50583 (
asymmetrical
)
12,197
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The synthesis of a number pyrrolo-annelated tetrathiafulvalenes, including the parent bis(pyrrolo[3,4-d])tetrathiafulvalene (7) is decribed. Starting from readily available 4,5-bis(bromomethyl)-1, 3-dithiole-2-thione (14) and sodium tosylamide, the parent 7 and the asymmetric monopyrrolo tetrathiafulvalenes 23a,b were prepared in good yields via a nonclassical and simple pyrrole synthesis. Furthermore, a series of
asymmetrical
N-alkylated monopyrrolo/monodihydropyrrolotetrathiafulvalenes was prepared starting from primary amines and 14. A detailed study of the fundamental redox behavior of this class of heterocycles is reported. NMR spectroscopy, cyclic voltammetry, and PM3 MO calculations revealed that the pyrrolo-annelated tetrathiafulvalenes have highly extended pi-surfaces. The X-ray crystallographic analyses of the monopyrrolo tetrathiafulvalenes 22b and 24b, together with preliminary formation of a charge-transfer complex between the parent donor 7 and
TCNQ
, are also reported.
...
PMID:Pyrrolo-annelated tetrathiafulvalenes: the parent systems 1097 Mar 26
Dithieno[2,3- d;2'3'- d']benzo[1,2- b;4,5- b']dithiophene forms mixed-stack charge-transfer complexes with fluorinated tetracyanoquinodimethanes (F
n
TCNQs, n = 0, 2, and 4) and dimethyldicyanoquinonediimine (DMDCNQI). The single-crystal transistors of the F
n
TCNQ
complexes exhibit electron transport, whereas the DMDCNQI complex shows hole transport as well. The dominance of electron transport is explained by the superexchange mechanism, where transfers corresponding to the acceptor-to-acceptor hopping ( t
e
eff
) are more than 10 times larger than the donor-to-donor hopping ( t
h
eff
). This is because the donor orbital next to the highest occupied molecular orbital makes a large contribution to the electron transport owing to the symmetry matching. Like this, inherently
asymmetrical
electron and hole transport in alternating stacks is understood by analyzing bridge orbitals other than the transport orbitals.
...
PMID:Carrier Charge Polarity in Mixed-Stack Charge-Transfer Crystals Containing Dithienobenzodithiophene. 2950 8
