1420-06-0Relevant articles and documents
Pyrrole-Based Anion-Responsive π-Electronic Molecules as Hydrogen-Bonding Catalysts
Hirata, Goki,Maeda, Hiromitsu
, p. 2853 - 2856 (2018)
The abilities of dipyrrolyldiketone boron complexes as hydrogen-bonding donor organocatalysts were examined by the Mannich-type reaction of N-acyl heteroarenium chlorides with 1-methoxy-2-methyl-1-trimethylsiloxy-1-propene, as well as by the classical N-alkylation of amines with trityl chloride under base-free conditions. 1H NMR examinations of the hydrogen-bonding interaction between the pyrrole NH of the catalyst and the Cl- in the N-acyl heteroarenium salt suggested that the activation of N-acyl heteroarenium chlorides occurs through anion binding by the catalyst.
Temporal control in tritylation reactions through light-driven variation in chloride ion binding catalysis-a proof of concept
Bari, Naimat K.,Grewal, Surbhi,Kumar, Himanshu,Roy, Saonli,Saraswat, Mayank,Sinha, Sharmistha,Venkataramani, Sugumar
, p. 7027 - 7033 (2020)
Tripodal triazole-linked azo(hetero)arene-based photoswitchable catalysts T1-5 have been designed, synthesized and optimized for the tritylation reaction of benzylamine (BzNH2). The tritylation reaction rates/yields achieved by light induced isomerization are compared between the native and photoswitched states of the catalyst T1. This concept of controlling the tritylation reaction rates with light has also been extended to additional substrates. The critical role of the triazole C-H?Cl- interactions has been confirmed by a combination of spectroscopic, calorimetric and computational studies. Also, the effect of variation in the binding affinities between the native and photoswitched states of the catalyst at room temperature in the temporal control of the catalysis has been demonstrated. This journal is
MELANIN PRODUCTION INHIBITOR
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Paragraph 0198 - 0202, (2015/12/17)
Disclosed is a melanin production inhibitor which has an excellent inhibitory activity on the production of melanin and is highly safe. The melanin production inhibitor is represented by general formula (1) (excluding clotrimazole) and/or a pharmacologically acceptable salt thereof. In the formula, A1, A2 and A3 are independently selected from a hydrogen atom, an aryl group which may have a substituent, and an aromatic heterocyclic group which may have a substituent. At least one of A1, A2 and A3 is selected from the aryl group and the aromatic heterocyclic group, the total number of carbon atoms contained in A1, A2 and A3 is 6 to 50 and, when at least two of A1, A2 and A3 represent the aryl groups or the aromatic heterocyclic groups, the adjacent two aryl or aromatic heterocyclic groups may be bound to each other via an alkyl chain or an alkenyl chain to form a ring; m represents an integer of 0 to 2; X represents a hetero atom, a hydrogen atom, or a carbon atom; R1 and R2 are independently selected from a hydrogen atom and an oxo group. When one of R1 and R2 is an oxo group, the other is not present. R3 is selected from a hydrogen atom, and a C1-8 hydrocarbon group in which one or some of hydrogen atoms or carbon atoms may be substituted by a hetero atom or hetero atoms. The number of R3's present in the compound corresponds to X and, when two or more R3's are present, the R3's are independently present and the adjacent two R3's may be bound to each other to form, together with X, a ring, and the terminal of R3 may be bound to a carbon atom to which A1, A2 and A3 are bound, thereby forming a ring.
