Synthesis of some N-[pyridyl(phenyl)carbonylamino]hydroxyalkyl-(benzyl)-1,2,3,6-tetrahydropyridines as potential anti-inflammatory agents

1,2,3,6-Tetrahydropyridines are known to possess analgesic, anti-inflammatory, hyperglycemic and hypoglycemic activities. Substituted 2,4-dinitrophenylpyridinium chlorides 3 were formed by reacting 1-chloro-2,4-dinitrobenzene with hydroxypropyl, hydroxymethyl and benzyl substituted pyridines 2 . Attack of the pyridinium chlorides 3 with pyridylcarbonyl hydrazides or benzoyl hydrazides 4 gave the isolable 2,4-dinitroanilino derivative 5 which underwent hydrolysis when refluxed in water:p-dioxane mixture (1:4 v/v) to afford the pyridinium ylides 6 . Sodium borohydride reduction of 6 in absolute ethanol at 0° for 4–6 hours resulted in the isolation of the 1,2,3,6-tetrahydropyridines 7 in good yields.     

Synthesis of some N-[pyridyl(phenyl)carbonylamino]-alkyl-1,2,3,6-tetrahydropyridines

Alkyl substituted 2,4-dinitrophenylpyridinium chlorides 3 are formed by the nucleophilic substitution of 1-chloro-2,4-dinitrobenzene with alkyl pyridines. Reaction of pyridyl acid hydrazides or benzoyl hydrazides 4 with the pyridinium chlorides 3 furnish the isolable 2,4-dinitroanilino derivatives 5 which undergo hydrolysis when refluxed in water:p-dioxane mixture (1:4 v/v) to yield the pyridinium ylides 6 . Sodium borohydride reduction of 6 in absolute ethanol at 0° for 4 hours result the formation of the title compounds 7 in moderate to excellent yields.     

Beitrag zur Klärung des Grossen Flusswiderstandes von Selengleichrichtern

The differential resistance of selenium rectifiers in the linear part of the V–I characteristic in the forward direction is considered; its value is three orders of magnitude higher than that of monocrystalline Ge-or Si-rectifiers and is closely connected with the current carrying capacity of selenium rectifiers. X-ray pictures showing the crystalline structure of selenium layers after heat treatment of different duration show increasing crystal growth in the polycrystalline selenium layer so that the differential resistance should be reduced. Measurement of the differential resistance, however, showed a gradual increase following an initial decrease, which is obviously connected with the process of ageing.     

Synthesis of N‐(substituted phenylcarbonylamino)‐4‐ethyl‐1,2,3,6‐tetrahydropyridines as potential nonsteroidal anti‐inflammatory agents

Fourteen novel N‐(substituted phenylcarbonylamino)‐4‐ethyl‐1,2,3,6‐tetrahydropyridines 9 were synthesized in fair to good yields. 4‐Ethylpyridine 5 reacted with O‐mesitylenesulfonylhydroxylamine (O‐MSH) 4 to furnish N‐amino‐4‐ethylpyridinium mesitylenesulfonate 6 . The reaction of 6 with substituted acid chlorides 7 gave the stable crystalline pyridinium ylides 8a‐8n . A sodium borohydride reduction of 8 in absolute ethanol furnished the target compounds N‐(substituted phenylcarbonylamino)‐4‐ethyl‐1,2,3,6‐tetrahydropyridines 9a‐9n .     

Synthesis and cytotoxic activity of some new 2,6-substituted purines

A seriesof twenty four acyclic unsaturated 2,6-substututed purines 5a-20b were synthesized. These compounds were evaluated for cytotoxic activity against NCI-60 DTP human tumor cell line screen at 10μMconcentration. N?-[(Z)-4'-chloro-2'-butenyl-1'-yl]-2,6-dichloropurine(5a), N?-[4'-chloro-2'-butynyl-1'-yl]-2,6-dichloropurine(10a), N?-[(E)-2',3'-dibromo-4'-chloro-2'-butenyl-1'-yl]-6-methoxypurine(14)and N?-[4'-chloro-2'-butynyl-1'-yl]-6-(4-methoxyphenyl)-purine(19)exhibited highly potent cytotoxic activity with GI?? values in the 1-5 μM range for most human tumor cell lines. Other compounds exhibited moderate activity.