Zur Kenntniss der Naphtoësäuren

Abstract

Wasser ausgewaschen und im Exsiccator getrocknet. Jedoch scheint die Oxydation nicht in glatter Weise vor sich zu gehen, da mehrere auf diese Weise dargestellte Proben des Farbstoffes bei der Analyse keine ubereinstimmenden Resultate ergaben.-Der Farbstoff ist ziemlich reichlich liislich in Wasser und Alkohol, fast unloslich in Aether. D r e s d e n , og.-chem. Laborat. von Prof. Schmitt. Znr Kenntniss der Naphtoesauren; von 8. G. Eckstrand. Die Naphtoesauren wurden in der von W i t t l) angegebenen W eise dargestellt. Fur grossere Bequemlichkeit und urn die Ausbeute an rohem Naphtonitril womijglich zu steigern , wandte ich zur Destillation des Gemenges von naphtalinsulfonsaurem Kalium oder Natrium und Ferrocyankalium eine flache, gusseiserne Pfanne an. Diese Pfanne hatte eine HBhe von 75 Mm. und eiiien inneren Durchmesser von 240 Mm. Der Deckel hatte denselben Durch-E c ks t r an d : Zur Kenntniss der Naphtoesauren. 14 1 1. 0,2901 Grm. gaben nach Schmelzen rnit Soda und Kalium-2. 0,2114 Grm. gaben, rnit Bleichromat uiid Sauerstoffgas ver-chlorat. 0,1617 Grrn. BaSO,. brannt, 0,6475 Grm. CO, und 0,0979 Grm. H,O.

SUBSTITUTED α-DIALKYLAMINOALKYL-1-NAPHTHALENE-METHANOLS. VIII. 5-, 6-, AND 7-CHLORO DERIVATIVES1

“…237-242°, sufficiently pure for further work. Two recrystallizations raised the melting point to 245°, which is that reported by Eckstrand (11).…”

“…A preliminary attempt to accomplish the proof by a Hofmann degradation of 6-chloro-l-naphthoic amide was not promising. For 5-chloro-l-naphthoic acid we chose the method of Eckstrand (11), involving chlorination of 1-naphthoic acid in glacial acetic acid. This gives a mixture of 5-chloro, 8-chloro, and 5,8-dichloro acids from which the 5-isomer can be separated readily as the ester.…”

“…The 8-chloro compounds fail to esterify by the Fischer procedure. Dichlorination can be largely prevented by chlorinating at room temperature for a limited time, but when the 5-isomer alone is desired, it is simpler to overchlorinate slightly at higher temperatures, which converts most of the 8-compound to 5,8-without removing much of the 5-derivative (11).…”

Aristoxazole Analogues. Conversion of 8-Nitro-1-naphthoic Acid to 2-Methylnaphtho[1,2-d]oxazole-9-carboxylic Acid: Comments on the Chemical Mechanism of Formation of DNA Adducts by the Aristolochic Acids

“…It is known that reduction of NNA ( 3 ) produces the lactam 5 {benz[ c,d ]indol-2(1 H )-one} by spontaneous cyclization of the reduction product 8-aminonaphthalene-1-carboxylic acid (reduction is instantly achieved by Fe 2+ ions in aqueous solution at room temperature). , In this study, reduction of NNA with Zn/HOAc at room temperature also yielded the expected lactam 5 . However, when the reaction is carried out in boiling acetic acid, in addition to lactam 5 , two new reduction products are formed, namely, the naphthoxazole 4 and the acetoxy derivative 6 .…”

“…NNA was synthesized by a literature procedure. 2 Zinc dust was purchased from Mallinckrodt (8681). NMR spectra were recorded on a Bruker 400 MHz FT-NMR spectrometer in DMSO-d 6 with TMS as internal standard.…”