23538-88-7Relevant articles and documents
Artemisinin derivative and intermediate, and preparation methods and applications thereof
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Paragraph 0256-0264, (2020/08/18)
The invention discloses an artemisinin derivative with a structure represented by a general formula (I), and a preparation method of the artemisinin derivative and application of the artemisinin derivative in preparation of antimalarial drugs, and further discloses an intermediate for preparing the artemisinin derivative and preparation of the intermediate.
New 1H-Pyrazole-Containing Polyamine Receptors Able to Complex L-Glutamate in Water at Physiological pH Values
Miranda, Carlos,Escarti, Francisco,Lamarque, Laurent,Yunta, Maria J. R.,Navarro, Pilar,Garcia-Espana, Enrique,Jimeno, M. Luisa
, p. 823 - 833 (2007/10/03)
The interaction of the pyrazole-containing macrocyclic receptors 3,6,9,12,13,16,19,22,25,26-decaazatricyclo-[22.2.1.1 11,14]-octacosa-1(27),11,14(28),24-tetraene 1[L1], 13,26-dibenzyl-3,6,9,12,13,16,19,22,25,26-decaazatricyclo-[22.2.1.1 11,14]-octacosa-1(27),11,14(28),24-tetraene 2[L2], 3,9,12,13,16,22,25,26-octaazatricyclo-[22.2.1.1 11,14]-octacosa-1(27),11,14(28),24-tetraene 3[L3], 6,19-dibenzyl-3,6,9,12,13,16,19,22,25,26-decaazatricyclo-[22.2.1.1 11,14]-octacosa-1(27),11,14,(28),24-tetraene 4[L4], 6,19-diphenethyl-3,6,9,12,13,16,19,22,25,26-decaazatricyclo-[22.2.1.1 11,14]-octacosa-1(27),11,14(28),24-tetraene 5[L5], and 6,19-dioctyl-3,6,9,12,13,16,19,22,25,26-decaazatricyclo-[22.2.1.1 11,14]-octacosa-1(27),11,14(28),24-tetraene 6[L6] with L-glutamate in aqueous solution has been studied by potentiometric techniques. The synthesis of receptors 3-6[L3-L6] is described for the first time. The potentiometric results show that 4[L4] containing benzyl groups in the central nitrogens of the polyamine side chains is the receptor displaying the larger interaction at pH 7.4 (Keff = 2.04 × 104). The presence of phenethyl 5[L5] or octyl groups 6[L6] instead of benzyl groups 4[L4] in the central nitrogens of the chains produces a drastic decrease in the stability [Keff = 3.51 × 102 (5), Keff = 3.64 × 102 (6)]. The studies show the relevance of the central polyaminic nitrogen in the interaction with glutamate. 1[L1] and 2[L2] with secondary nitrogens in this position present significantly larger interactions than 3[L3], which lacks an amino group in the center of the chains. The NMR and modeling studies suggest the important contribution of hydrogen bonding and π-cation interaction to adduct formation.
Doubly and Triply Bridged Polyoxapolyazaheterophanes Derived from 2,4,6-Trichloro-s-triazine
Anelli, Pier Lucio,Lunazzi, Ludovico,Montanari, Fernando,Quici, Silvio
, p. 4197 - 4203 (2007/10/02)
Doubly and triply bridged polyoxapolyazaheterophanes (1, 2) have been synthesized from 2,4,6-trichloro-s-triazine by using the different reactivity of the three chlorine atoms toward neutral nucleophiles.Introduction of alkyl groups and/or of heteroatoms in the bridging chains makes these systems soluble in organic solvents.Triazinophanes 1h and 2b, with NH groups in the bridging chains, may be used as phase-transfer catalysts in nucleophilic aliphatic substitutions. 13C NMR spectra indicate that molecules 1 and 2 either exists in a single nonsymmetric conformation up to about room temperature or, more likely, that there are two or more differently populated conformations separated by a high interconversion barrier.