Porphyrins with exocyclic rings. Part 8. Synthesis of nitrogen-15 and carbon-13 labeled 2,3:7,8:12,13:17,18-tetrabutanoporphyrin
作者:Shaohua Chen、Timothy D. Lash
DOI:10.1002/jhet.5570340141
日期:1997.1
Nitrogen-15 labeled butyl 4,5,6,7-tetrahydro-2H-isoindoIe-1-carboxylate was prepared via butyl iso-cyanoacetate from 15N-glycine in an overall 46% yield. This bicyclic intermediate was converted into nitrogen-15 and carbon-13 labeled 2,3:7,8:12,13:17,18-tetrabutanoporphyrin, a useful model system for the sedimentary tetrahydrobenzoporphyrins.
A series of α-isocyanoacrylic acid derivatives were prepared via the α-formylaminoacrylic acid derivatives, which were obtained by the reaction of isocyanoacetic acids and carbonyl compounds, in order to examine their antimicrobial activities. The structureactivity relationships are presented ; it was found that (Z)-α-isocyanoacrylic acid esters possessing halogeno phenyl or thienyl groups exhibited fairly strong antifungal activities. Of these, (Z)-methyl α-isocyano-β-(2-thienyl) acrylates (5s and 5u) showed the highest activity (1.56μg/ml MIC) against Tricophyton mentagrophytes.
2-haloaryl isothiocyanates and isocyanides to access benzo[d]imidazo[5,1-b]thiazoles has been realized efficiently under metal- and photocatalyst-free conditions. The reaction mechanism was explored by several preliminary experiments involvingreactive intermediate, free radical inhibitors, and corresponding photoelectric spectra. This protocol possesses some advantages over the previous methods such as
在无金属和无光催化剂的条件下,已经有效地实现了可见光促进的2-卤代芳基异硫氰酸酯和异氰酸酯的级联环化反应,以接近苯并[ d ]咪唑并[5,1- b ]噻唑。通过涉及反应性中间体,自由基抑制剂和相应的光电光谱的几个初步实验探索了反应机理。该方案相对于先前的方法具有一些优势,例如易于获得和廉价的底物,无金属催化剂,步骤和原子经济,反应条件温和。
Copper‐Catalyzed [3+2] Cycloaddition Reactions of Isocyanoacetates with Phosphaalkynes to Prepare 1,3‐Azaphospholes
heterocycles such as 1,3‐azaphospholes. Cycloaddition reactions of various isocyanoacetates with phosphaalkynes in the presence of copper bromide, bis(diphenylphosphino)methane (dppm), and potassium carbonate afford the corresponding 1,3‐azaphospholes in high yields with complete selectivity. Some dppm‐bridged dicopper complexes were identified as active species for the formation of 1,3‐azaphospholes.
Enhanced mechano-responsive fluorescence in polydiacetylene thin films through functionalization with tetrazine dyes: photopolymerization, energy transfer and AFM coupled to fluorescence microscopy studies
development of mechano-responsive fluorescent materials is essential for the design and construction of reliable and versatile sensors for mechanical stress. Herein, novel energy transfer-based systems with tetrazine fluorophore and a polydiacetylene (PDA) backbone are synthesized and studied comparatively to a simple polydiacetylene in the form of thinfilms. Their photopolymerization properties, energy