Biological Evaluation and Binding Mechanism of 5-HT7 Specific Arylpiperazinyl-Alkyl Benzothiazolone: Radiobiology and Photo-physical Studies

J Fluoresc. 2024 Jan;34(1):341-352. doi: 10.1007/s10895-023-03266-4. Epub 2023 May 30.

Abstract

Diversely substituted methoxy derivatives of arylpiperazinyl-alkyl benzothiazolone has been evaluated as specific probe for 5HT7. To determine the best methoxy derivative for 5HT7 receptor affinity, we synthesised a number of 2-benzothiazolone arylalkyl piperazine derivatives. In-vitro/vivo studies with C-2 substituted [11C]ABT showed 5HT7 specific binding. The radiochemical purity of [11C]ABT was found to be more than 99% with radiochemical stability persistence for more than 1.5 hr at 25 °C. The interaction of BSA and ABT has been analysed by photophysical studies for better understanding of properties such as adsortion, distribution, metabolism and elemination (ADME). The interaction between ABT and BSA was analyzed by using the UV-vis and fluorescence spectra. UV-vis spectra analyzed the changes in primary structure of BSA on its interaction with ABT. ABT showed quenched fluorescence emission intensity of tryptophan residues in BSA via static quenching mechanism. This study might help to understand how ABT binds to serum protein or subsequently to know the ADME of this drug candidate.

Keywords: 5HT7; Arylpiperazinyl–alkyl benzothiazolone; BSA; Circular dichroism spectroscopy; Fluorescence; UV-vis spectroscopy.

MeSH terms

  • Circular Dichroism
  • Protein Binding
  • Radiobiology
  • Serotonin* / metabolism
  • Serum Albumin, Bovine* / chemistry
  • Spectrometry, Fluorescence
  • Thermodynamics

Substances

  • Serum Albumin, Bovine
  • Serotonin