XXXVIII.—The methoxyindoles and their derivatives

Regeneration of Carbonyl Compounds from the Corresponding Oximes

“…Sulfur dioxide was also used, initially in cold hydroalcoholic solution and subsequently with light heating until the disappearance of the oxime. 34…”

7‐Methoxyindole and its Derivatives

“…

7-Methoxyindole was prepared by reductive cyclization of 3-methoxy-2, B-dinitrostyrene. The synthesis and pharmacological properties of several 7-methoxytryptamines are described.Methoxyindole derivatives substituted at position 7 attracted our attention because they are related to several Vinca alkaloids known to possess interesting biological activities [1].The parent compound, 7-methoxyindole (I) was prepared earlier by decarboxylating 7-methoxy-2-indolecarboxylic acid [2][3][4]. The formation of (I) by methylation of 7-hydroxyindole has been described by Japanese workers [5], and, more recently, after the completion of this work, the preparation of (I) from 7-methoxyindoline has been reported [6].The following reactions have also been applied for the preparation of compounds in the desired series: The Fischer cyclization of o-methoxyphenylhydrazone of "Y-aminobutyraldehyde gave 7-methoxytryptamine [7]: the synthesis of 7-methoxytryptophan was realized with 7-methoxyindole-3-aldehyde and hydantoin [2,3], or with 7-methoxyindolylmagnesium bromide and chloromethylenehydantoin [8].

…”

“…The synthesis and pharmacological properties of several 7-methoxytryptamines are described.Methoxyindole derivatives substituted at position 7 attracted our attention because they are related to several Vinca alkaloids known to possess interesting biological activities [1].The parent compound, 7-methoxyindole (I) was prepared earlier by decarboxylating 7-methoxy-2-indolecarboxylic acid [2][3][4]. The formation of (I) by methylation of 7-hydroxyindole has been described by Japanese workers [5], and, more recently, after the completion of this work, the preparation of (I) from 7-methoxyindoline has been reported [6].The following reactions have also been applied for the preparation of compounds in the desired series: The Fischer cyclization of o-methoxyphenylhydrazone of "Y-aminobutyraldehyde gave 7-methoxytryptamine [7]: the synthesis of 7-methoxytryptophan was realized with 7-methoxyindole-3-aldehyde and hydantoin [2,3], or with 7-methoxyindolylmagnesium bromide and chloromethylenehydantoin [8]. Fischer cyclization of ')' -acetamido-')', v : diethoxycarbonylbutyraldehyde 2-methoxyphenylhydrazone [9], and the reaction of 7-methoxygramine with diethyl acetamidomalonate [10], were also reported.Since the yields of the products reported were low and the methods cumbersome we decided to try a method based on the reduction of 2, -dinitrostyrenes [11,12], and which has been successfully applied by us for the preparation of fluoroindoles, e. g., [13].…”

“…The parent compound, 7-methoxyindole (I) was prepared earlier by decarboxylating 7-methoxy-2-indolecarboxylic acid [2][3][4]. The formation of (I) by methylation of 7-hydroxyindole has been described by Japanese workers [5], and, more recently, after the completion of this work, the preparation of (I) from 7-methoxyindoline has been reported [6].…”

“…The following reactions have also been applied for the preparation of compounds in the desired series: The Fischer cyclization of o-methoxyphenylhydrazone of "Y-aminobutyraldehyde gave 7-methoxytryptamine [7]: the synthesis of 7-methoxytryptophan was realized with 7-methoxyindole-3-aldehyde and hydantoin [2,3], or with 7-methoxyindolylmagnesium bromide and chloromethylenehydantoin [8]. Fischer cyclization of ')' -acetamido-')', v : diethoxycarbonylbutyraldehyde 2-methoxyphenylhydrazone [9], and the reaction of 7-methoxygramine with diethyl acetamidomalonate [10], were also reported.…”