Sentences with word «substituent»

We are exploring the conformational properties of the tetraarylporphyrine core structure with different substituents of increasing size and molecular weight.

Despite being highly useful, multi-substituted benzene derivatives are rather difficult to synthesize due to the lack of selective methods to install different substituents at the desired positions.

Various synthetic approaches for the introduction of substituents on these indoles are available.

All the data reported in this study indicate that introductions of aromatic and basic substituents on amino acid side chains are useful to determine the antagonists / CXCR4 binding mode on the cell membrane.

The presence of halogen substituents in many bioactive compounds has a profound influence on their molecular properties.

And 20 minutes in those games to come in as substituents.

This development could find broad applications in pharmaceutical and agricultural industries, enabling medicinal chemists to tailor synthetic molecules with halogen substituents in order to improve their pharmacological profiles.

Itami and Yamaguchi's programmed synthesis has enabled the synthesis of HABs bearing five or six different substituents for the first time.

Other substituents did not significantly affect the potency of these derivatives (103, 104).

Amino acids were added to the phenyl substituent present on the pendent amine in the second coordination sphere of the nickel center.

Cellulose functions depend on what type and how many substituents are attached.

In the new study, he introduces a synthetic molecule which folds into a helical structure that mimics surface features of the DNA double helix, and whose precise shape can be altered in a modular fashion by the attachment of various substituents.

Formula milk, although a good substituent, can certainly not provide the same benefits as breast feeding.

The protocol furnished a diverse array of benzofuran products with a B substituent conveniently poised for further reactivity via Suzuki coupling or other elaborations.

Although there are a vast number of possible substituents that could be attached to benzene, many of the functional hexaarylbenzenes (HABs) possess a symmetrical structure.

«Larger groups would cause the rings to move closer together, shifting the color to the orange - yellow range, while smaller substituents would make the rings move apart, turning the emission color red.

In biochemistry, this term refers to alpha - amino acids with the general formula H2NCHRCOOH, where R is an organic substituent.

The picture shows the overlay of the microscopic image of Hapaloshiphon welwitschii UTEX B1830, the producer strain of 12 - epi - hapalindole E and 12 - epi - fischerindole G, of which the chlorine substituents (shown red) were installed by the WelO5 protein — the newly discovered halogenation enzyme.

To improve solubility, Itami and his colleagues have developed warped nanographene molecules with chemical substituents at the outer rim of the aromatic structure.

Among several molecular scaffold candidates, 5 - aminoindole -2-carboxylic acid was selected since molecular modeling experiments showed that it meets the spatial requirements for the three key substituents.

Further modifications focused on the replacement of the side chain methyl group with several alternative substituents.

The introduction of a N - amidinopiperidine -4-carbonyl substituent was also acceptable for a higher potency (IC50 (41) = 3.0 μM).

Furthermore, theoretical calculations on diphosphine capped gold clusters often involve the substitution of simpler hydrogen atoms in the place of computationally demanding substituents such as phenyl groups with the assumption that the substitution does not alter the stability of the cluster.

Many studies performed on the effects of red maca on our system show that the herb is a potent substituent to anabolic steroids, which are more detrimental to one's health.

Among the halogen substituents at position 4 of the phenyl ring within D - Phe2, fluorine showed to be optimal, since chlorine and bromine, or even a nitro group, negatively affected the activity profile of 26, 27, 28 and 29 (IC50 = 0.035, 0.79, 0.57 and 0.94 μM, respectively).

When the amino acid was added in the para position of the phenyl substituent, the overpotential was much higher than when it was added in the meta position.

The six hydrogens can be replaced by different substituents, making benzene an extremely versatile building block in many materials including in pharmaceuticals, agrochemicals, plastics and organic electronic devices.

[Ni (PPh2NC6H4X2) 2] 2 + Complexes as Electrocatalysts for H2 Production: Effect of Substituents, Acids, and Water on Catalytic Rates.»

The reaction has a broad substrate scope, tolerant to various different substituents, enabling facile synthesis of a variety of indene derivatives.

Attaching optical fluorescent molecules, or chromophores, to biological substrates is common in cell - imaging studies, but these substituents are large and often interfere with cell metabolism, damaging the cells.

Based on Burnside's counting theorem, the number of possible substituted benzenes (N) from n different substituents is (2n + 2n ^ 2 + 4n ^ 3 + 3n ^ 4 + n ^ 6) / 12.

For example, with 10 substituents, the number of possible substitution patterns on benzene will be 86,185.

«After numerous attempts to find the right reaction conditions, we were finally able to obtain the crystal structure of a propeller - shaped, radially extended HAB with six different substituents.»

Analysis of these novel unsymmetrical compounds revealed that the otherwise non-fluorescent hexaphenylbenzene could actually be made fluorescent by tuning the substituents on the exterior.

Once the molecule is borylated, the boron substituent can be replaced by other substituents, in this case, by an aromatic molecule bearing highly soluble tetra (ethylene glycol) chains (TEG).

The substituents were introduced by the relatively simple and powerful strategy of borylation.

The order of preference among halogen atoms as a substituent at position 4 of D - Phe1 was shown to be F then Cl then Br, resulting in the following order of activity: 16 > 20 > 21 (IC50 = 0.22, 1.2 and 2.3 μM, for the three halogen - containing derivatives, respectively)(Table 1).

In contrast, the substituents (e.g., phenyl (C6H5)-RRB- at the two phosphorus centers are generally regarded as not exerting an influence on the selectivity of diphosphine ligands towards gold clusters of a particular size.