Spirobipyrane aus o‐Hydroxyarylvinylpyryliumsalzen

Abstract

Spirobipyrans from o-Hydroxyarytvinylpyrylium SaltsStructurally defined o-hydroxyarylvinylpyrylium salts can be cyclized to spirobipyrans of type 1-5 and to the hitherto unknown 2,2'-spirobi[ZH-naphtho[l ,Z-b]pyrans] (6). Asymmetric monosubstituted spirobipyrans of type 2,3, and 5 show a correlation between thermochromism and position of the substituent (Table I).Trotz einer relativ grokn Zahl von Untersuchungen iiber das Verhalten von Spirobipyranen wurde bislang nur wenig iiber einfach substituierte Spirobipyrane bekannt. Nachdem wir iiber die Eigenschaften strukturspezifisch aufgebauter o-Hydroxyarylvinylpyryliurnsalze berichteten 1.2), sollen hier die Daten einiger aus diesen dargestellter Spirobipyrane vom Typ 1-6 rnitgeteilt werden. Von diesen waren unseres Wissens 2.2'-Spirobi[2H-naphtho[ 1.2-blpyraneI (6) bisher unbekannt.

Benzopyrylium salts as new anticancer, antibacterial, and antioxidant agents

“…Two out of the five synthesized compounds are novel. The compounds PS-CP-SAL [6,11], PS-CP-4MO [11], and PS-CP-5Br [9] have already been reported previously though their biological activities have not been evaluated till date. The UV-vis spectra show three distinctive peaks, foremost in between 250 and 260 nm, followed by the subsequent peak in the range of 290 and 320 nm and the final peak between 400 and 530 nm.…”

“…In this study, we focus on a specific class of pyrylium salts, i.e., the benzopyrylium salts. The synthesis of some napthopyrylium salts have already been reported and studied for thermochromic and photochromic properties [6][7][8][9]. On the other hand, the benzopyrylium salts were first reported by Borche and Geyer [10] in 1913 and not many studies been carried out for these kind of benzopyrylium salts.…”

Synthesis, Characterization, In‐Vitro and In‐Vivo Anti‐Cancer Evaluation of Novel Benzopyrylium Salts on Colorectal Cancer Model of Drosophila Melanogaster

“…Additionally, pyrylium salts are employed as constituent dyes in lasers [6] and have been the subject of research regarding their photochromic properties. [7][8][9][10] With the advent of photodynamic therapy, pyrylium salts have also been explored for their biological activities. It has been reported that thiopyrylium dye inhibits proliferation of human colon carcinoma cell line CX1.…”

“…These salts serve a crucial role in the photographic industry, functioning as markers on photographic rolls due to their distinct fluorescence and color under UV light. Additionally, pyrylium salts are employed as constituent dyes in lasers [6] and have been the subject of research regarding their photochromic properties [7–10] . With the advent of photodynamic therapy, pyrylium salts have also been explored for their biological activities.…”

Ultraviolet spectrometry

“…Since the data are given for compounds representative of classes, they are often useful to analytical chemists. Tables consisting of more than 20 compounds and of interest include substituted azines (108), ureidohydrofurans and related pyrimidones (52), ring-opened analogs of cyclopropylpyridines (155), 4-hydroxy-6-phenylpyrazols [3,4-d]pyrimidines (20), 6-aryl-7-aminopteridines (397), 2,4,7-triamino -6 -het eroary lpteridines (398), derivatives of naphth [2,3-d]imidazole-4,9-dione (105), spirobipyranes (341), pyrazolo- [4,[3][4][5][6] [l,4]-thiazine condensed ring systems (162), pyrazolo-(4,3-¡7-]-pteridines and derivatives (161), Ar-substituted derivatives of 2-benzothiazolinethione (357), phosphinimines (382), substituted-s-trizaolo [4,3-a] pyrazines and -quinoxalines (315), alkyl-6-(4-carboxybutylthio) purines ( 227), benzimidazole derivatives (206), quinoxaline derivatives (296), 8-azapurines (6), ketimines (9), pteridines, pyrimidines, and isoalloxazines (331), substituted pyridones, pyridines, and pyridinethiones (45), pyrrolizidine alkaloids (350), derivatives of phenothiazine (229) , o-acylphenols (261), p-acylphenols (260), stilben and styryl derivatives (347), derivatives of glyoxal bisarylhydrazones (109), nitrophenylhydrazones (321), 3,4-dihydrocoumarins (386), 4-hydroxy coumarins (267), aromatic aldehydes and acetophenones (82), and disubstituted 1,4-benzoquinone-4-oximes (289).…”