<p>Aim and Objective: This work presents the synthetic capability and the exploitation of 1,3-diphenyl-
1H-pyrazole-4-carboxladehyde 1 and 5-diphenyl pyrazolyl-2-pyrazoline analogue 8 to serve as excellent
precursors for the synthesis of substituted indol-2,3-dione, trizolo[3,4-a]benzazoles, thiazolo[2,3-
a]benzimidazole-3-one, substituted 2-pyrazoline and pyrazole-substituted-pyrazolines using various reagents.
</P><P>
Materials and Methods: Using chemicals from Aldrich, Fluka, or Merck, and pure solvents, we apply the
synthetic procedures for the synthesis of novel heterocycles. The melting points of these compounds were determined
using APP. Digital ST 15 melting point apparatus. SP3-100 spectrophotometer recorded FT-IR spectra
(KBr) (cm-1). NMR spectra (δ, ppm) were recorded on 400 MHz AVANCE-III High-Performance
FT-NMR Spectrometer BRUCKER (Switzerland) and some 1H NMR spectra were recorded on Varian
EM-360L NMR Spectrophotometer (90 MHz) (USA) in CDCl3 or DMSO-d6 as a solvent. Elemental analyses
were carried out at a Vario EL C, H, N, and S Analyzer. Bromine was determined using direct titration method
after carius combustion.
</P><P>
Results: The structures of the compounds were confirmed by IR, 1H NMR, 13C NMR, and elemental analyses.
</P><P>
Conclusion: 1,3-Diphenyl-1H-pyrazole-4-carboxladehyde 1 and 2-pyrazoline derivative 9 confirmed their
importance in the synthetic organic chemistry. Depending on the formyl group of aldehyde 1 and active
methylene of pyrazoline 8, we synthesized new series of heterocycles; indol-2,3-dione, trizolo[3,4-a]benzazole,
thiazolo[2,3-a]benzimidazole-3-one and pyrazolyl-pyrazoline derivatives expecting their pharmacological applications.
The targeted compounds were substantiated from its spectral data.</p>