Construction of a six-membered fused N-heterocyclic ring via a new 3-component reaction: synthesis of (pyrazolo)pyrimidines/pyridines

Kumar, P. Anil; Kumar, Kapil; Mohakhud, P. K.; Mukkanti, K.; Kapavarapu, Ravikumar; Parsa, Kishore V. L.; Pal, Manojit

doi:10.1039/c1cc16418j

Cited by 52 publications

(23 citation statements)

References 16 publications

(5 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results suggest that both stem base pair composition and the sequence context influence ligand binding parameters. This finding supports our recent [14] and other group's [15] observations that demonstrated importance of stem regions in another class of aptamer on ligand binding affinity. We mutated U61 in aptamer 15 to obtain aptamer 16.…”

Section: Methodssupporting

confidence: 92%

Tuning Riboswitch‐Mediated Gene Regulation by Rational Control of Aptamer Ligand Binding Properties

2014

View full text Add to dashboard Cite

Riboswitch-mediated control of gene expression depends on ligand binding properties (kinetics and affinity) of its aptamer domain. A detailed analysis of interior regions of the aptamer, which affect the ligand binding properties, is important for both understanding natural riboswitch functions and for enabling rational design of tuneable artificial riboswitches. Kinetic analyses of binding reaction between flavin mononucleotide (FMN) and several natural and mutant aptamer domains of FMN-specific riboswitches were performed. The strong dependence of the dissociation rate (52.6-fold) and affinity (100-fold) on the identities of base pairs in the aptamer stem suggested that the stem region, which is conserved in length but variable in base-pair composition and context, is the tuning region of the FMN-specific aptamer. Synthetic riboswitches were constructed based on the same aptamer domain by rationally modifying the tuning regions. The observed 9.31-fold difference in the half-maximal effective concentration (EC50) corresponded to a 11.6-fold difference in the dissociation constant (K(D)) of the aptamer domains and suggested that the gene expression can be controlled by rationally adjusting the tuning regions.

show abstract

Section: Methodssupporting

confidence: 92%

Tuning Riboswitch‐Mediated Gene Regulation by Rational Control of Aptamer Ligand Binding Properties

2014

View full text Add to dashboard Cite

show abstract

“…However, the azomethine band at 1630 cm -1 in I reduced by 20 cm -1 in compounds. The shift of this band shows the coordination of azomethine N atom [21].…”

Section: Resultsmentioning

confidence: 92%

“…The band at 1680 cm -1 due to the ν(C=O) of DMF shows a negative shift by 30 cm -1 in the compound. It indicates the coordination of DMF through this O atom [21].…”

Section: Resultsmentioning

confidence: 96%

See 1 more Smart Citation

Preparation and Spectroscopic Characterization of Polymer-Supported Transition Metal Complexes

Gupta

Kumar

Kumar³

2019

Asian J. Chem.

View full text Add to dashboard Cite

Novel polystyrene supported mixed Schiff base (PSCH2–LH2) and its coordination compounds with copper(II) and zirconium(IV) have been synthesized. PSCH2–LH2 has been synthesized by the reaction of chloromethylated polystyrene crosslinked with divinylbenzene (PSCH2–Cl) and the Schiff base (LH2) derived from 3-formylsalicylic acid, propylenediamine and acetylacetone. The polystyrene supported coordination compounds are of the types: [PSCH2–LCu] and [PSCH2–LZr(OH)2·DMF]. They have been synthesized by the reaction of PSCH2–LH2 and the metal salt in DMF. The coordination compounds have been characterized on the basis of elemental analyses, IR, reflectance, ESR spectral and magnetic susceptibility measurements. The shifts of the ν(C=N) (azomethine), ν(C–O) (phenolic) and ν(C–O) (enolic) stretches indicate the ONNO donor behaviour of PSCH2–LH2. The polystyrene supported Cu(II) compound is square planar and Zr(IV) compound is pentagonal bipyramidal. The coordinated solvent molecules are completely lost from metal bound coordination compound by heating them at definite temperature in an air oven for 3 h. The compound, PSCH2–LCu is paramagnetic, while PSCH2–LZr(OH)2·DMF is diamagnetic.

show abstract

“…14.8, 96.4, 104.3, 127.1, 128.6, 128.8, 129.2, 130.0, 130.8, 131.6, 137.6, 146.1, 150.6, 155.4, 155.7;IR (CHCl 3 , cm -1 ): 771, 1017, 1218, 1373, 1490, 1554, 1608, 2924MS (EI, m/z) C,79.98;H,5.30;N,14.73. Found: C,79.81;H,5.59;N,14.89. 4, 32.9, 93.0, 104.0, 127.1, 128.3, 128.8, 129.4, 129.9, 130.7, 131.6, 137.8, 145.9, 150.4, 155.4, 168.0;IR (CHCl 3 , cm -1 ): 762, 1017, 1239, 1490, 1551, 1606, 2960MS (EI, m/z) 3 : C,80.70;H,6.46;N,12.83.…”

Section: General Procedures For the Synthesis Of Pyrazolo[15-a]pyrimimentioning

confidence: 98%

Carbon–Carbon Bond Cleavage Reaction: Synthesis of Multisubstituted Pyrazolo[1,5-a]pyrimidines

2015

View full text Add to dashboard Cite

show abstract

Construction of a six-membered fused N-heterocyclic ring via a new 3-component reaction: synthesis of (pyrazolo)pyrimidines/pyridines

Abstract: A conceptually new three-component reaction was developed to construct a six-membered fused N-heterocyclic ring affording (pyrazolo)pyrimidines/pyridines as potential inhibitors of PDE4. The reaction is catalyzed by triflic acid in acetic acid in the presence of aerial oxygen.

Cited by 52 publications

References 16 publications

Tuning Riboswitch‐Mediated Gene Regulation by Rational Control of Aptamer Ligand Binding Properties

Tuning Riboswitch‐Mediated Gene Regulation by Rational Control of Aptamer Ligand Binding Properties

Preparation and Spectroscopic Characterization of Polymer-Supported Transition Metal Complexes

Carbon–Carbon Bond Cleavage Reaction: Synthesis of Multisubstituted Pyrazolo[1,5-a]pyrimidines

Contact Info

Product

Resources

About