Synthesis and rearrangement of 5-phenyl-7-methoxy-2,4,9-trioxo-1,3-diazabicyclo[3.3.1]nonane

Abstract

The synthesis and proof of structure of the bicyclobarbiturate, 5-phenyl-7-methoxy-2,4,9-triketo-l,3-diazabicyclo[3.3.1 ¡nonane (2), is described. An attempt was made to demethylate 2 utilizing boron trichloride and resulted in the formation of a -lactone. A plausible mechanism for this transformation is given.A study of the steric aspects of antiepileptic drug action was initiated by investigating the synthesis of bridged barbituric acids (1).

Condensation of 2,4-diamino-6(1H)-pyrimidinone with 2-(aminomethylene)cyclopentanone

“…2-Amino-3-carbethoxy-5,6-trimethylenepyridine (6). A suspension of 2.0 g of 4 in 25 mL of saturated ethanolic ammonia was stirred at room temperature for 96 h, and the resulting precipitate of 5 was collected by filtration and recrystallized from acetic acid: yield 1.35 g (88%), mp 323-324 °C.…”

“…Chem., submitted for publication. (6) In footnote a to that "Aufgrund neuerer Messungen der 13€-Kopplungskonstanten an den Cycloalkeno-5-desazapteridinen und analogen Verbindungen ist nicht auszuschliessen, dass die Zuordnung der 13C-Signale von C-5 und C-7 in Abb. 2 und den Tab.…”

“…2 und den Tab. [4][5][6] umzukehren ist. Dementsprechend ware der Cycloalkenring in den Verbindungen 12-14 und 17-21 linear, d.h. in 6,7-Stellung des 5-Desazapteridins ankondensiert".…”

N-Acylcarbamates as intermediates in synthetic approaches to a bicyclic trimethylene-bridged 2,4-oxazolidinedione and hydantoin

“…Carbamate 13 was prepared from 3-phenyl-2-piperidinone (11), which was available from another study in these laboratories. 13 Lactam 11 was acylated with ClC02Et in toluene at reflux to give carbamate at temperatures lower than 180 °C resulted in recovered starting material, while heating at 180 °C for 4 h did not yield la but gave a product for which the IR spectrum contained one major carbonyl absorption at 1670 cm-1.…”

Intramolecular isomerizations of 5-phenyl-5-(3-aminopropyl)barbituric acids

“…As part of a continuing study on the steric requirements for selective central nervous system depression, attempts have been made to develop general synthetic routes to bridged barbituric acids 1, to be investigated as antiepileptic agents. Although attempts to prepare such ring systems have met with great difficulty, one such barbituric acid, 5-phenyl-7-methoxy-2,4,9-triketo-l,3-diazabicyclo[3.3.1]nonane (2), has been prepared.2 Its synthesis was accomplished via an intramolecular imide attack on the primary bromide function of 5-phenyl-5-(2-methoxy-3-bromopropyl)barbituric acid (3). This procedure did not prove to be a general method for the desired compounds, since similar intramolecular alkylations of 5-phenyl-5-(3-halopropyl)-and 5-(2-halopropyl)barbituric acids yielded the O-alkylated pyrano-and furopyrimidines 4 and 5, rather than the N-alkylated systems.…”