Total Synthesis and Proof of Stereochemistry of Natural and Unnatural Pinnaic Acids: A Remarkable Long-Range Stereochemical Effect in the Reduction of 17-Oxo Precursors of the Pinnaic Acids This work was supported by the National Institutes of Health (Grant Numbers: CA28824). Postdoctoral Fellowship support is gratefully acknowledged by M.W.C. (U.S. Army BCRP, DAMD17-98-1-8154). We thank Dr. George Sukenick of the MSKCC NMR Core Facility for NMR and mass spectral analyses. We would like to thank professor Nakanishi for his supportive interest in the project.

2001 ◽  
Vol 40 (23) ◽  
pp. 4453 ◽  
Author(s):  
Matthew W. Carson ◽  
Guncheol Kim ◽  
Samuel J. Danishefsky
Keyword(s):  
Total Synthesis ◽  
Long Range ◽  
National Institutes Of Health ◽  
Spectral Analyses ◽  
Mass Spectral ◽  
Postdoctoral Fellowship

Synthesis of Novel Bis-pyrazoles via Electrophilic Cyclization

2019 ◽  
Vol 16 (6) ◽  
pp. 511-516
Author(s):  
Adnan Cetin
Keyword(s):  
13C Nmr ◽  
Cyclization Reaction ◽  
Electrophilic Cyclization ◽  
Pyrazole Derivatives ◽  
Spectral Analyses ◽  
Mass Spectral ◽  
Palladium Catalyzed ◽  
Ft Ir ◽  
Reaction Compound

Efficient steps towards the synthesis of novel (phenyl)(1'-aryl-1,5,5'-triphenyl[3,3'-bi-1Hpyrazol]- 4-yl)methanones 4a-e were developed. The procedure starts from 1-(4-benzoyl-1,5-diphenyl- 1H-3-pyrazolyl)-3-phenyl-2-propyn-1-one (2) which was synthesized by a palladium catalyzed crosscoupling reaction. Compound 2 reacted with various hydrazines to give (E)-(phenyl)[1,5-diphenyl-3- [3-phenyl-1-(2-arylhydrazono)-2-propyn-1-yl]-1H-4-pyrazolyl]methanones E-3a-e. The bis-pyrazole derivatives 4a-e were synthesized from electrophilic cyclization reaction of α,β-acetylenic hydrazones E-3a-e and copper(I) iodide. All synthesized compounds were characterized by FT-IR, 1H, 13C NMR and Mass spectral analyses.

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