5158 xz greater than xl, it was possible to submit the isolated product 1 (with [WID) obtained from the experiment with an extent of reaction of XI to a further photolysis under the same conditions. In this way, if a photolysis of reaction extent x' is achieved from this already optically active product l ( [ a l ]~) the remaining product has a new optical rotatory power ([az]D). The corresponding extent of reaction xz of the photolysis starting with (f)-1 is given byThis procedure was also used by Mitchell.z6 We checked that the enantiomeric purity of the remaining compound in the partial photoresolution was the same either by achieving directly the reaction extent XZ, or by achieving x1 and then x ' , separately. This procedure was used in the photolysis of both a-azido-N,N-dimethylpropionamide and camphor.(+)-Camphor. Racemic camphor provided by the Delaire Co. (France) was recrystallized twice from hexane and then sublimed. Its glc analysis showed a purity greater than 99% and the optical activity was [ a I z 6~ -0.14" (c 6, hexane).This racemic camphor was obtained by a synthesis starting from naturally occurring optically active a-pinene and since one of the steps of this synthesis was a racemization, the slight residual optical activity observed in the final product was probably due to incomplete racemization.A sample of camphor ( [ a ]~ -0.14") purified by the above procedure was submitted to preparative glc, and there was no difference in the specific rotation of the highly purified camphor collected. The presence of an optically active impurity was therefore ruled out, so that the slight optical activity observed was due to an enantiomeric excess of 0.25% in the camphor. For our experiments requiring completely racemic material, we adjusted the rotatory power of the nearly racemic compound to [a]D 0.005 f 0.005' by the addition of optically pure (+)-camphor [[aIz51) +52.9" ( c 2.5, hexane)].Partial Kinetic Photoresolution of Racemic Camphor. A solution cis-Azoxyalkanes.Resonance Spectral of 6 g of racemic camphor in 360 ml of n-hexane was placed in the irradiation cell (diameter 100 mm, volume 360 ml) which was closed with a glass stopper and magnetic stirring was maintained during the course of the irradiation. For the determination of the extent of the photodecomposition, 1-ml samples were taken, a known weight of a standard (n-hexadecane) was added, and the mixture was analyzed by glc (column A temperature 120", carrier Nz 25 mlimin); thus, the disappearance of camphor was determined by measurement of the peak areas of camphor and the standard. When the desired extent of reaction had been achieved the irradiation was stopped. The solvent then was carefully removed avoiding sublimation of remaining camphor which was separated from the mixture of photoproducts by preparative glc (column B temperature 145", carrier N 1 100 mlimin). Two such purifications by glc were necessary and the purified camphor was used for the determination of the optical purity. The optical rotatory power was measured in n-hex...

The synthesis of a variety of pyrrolo[1,2-c]quinazolines and pyrrolo[1,2-c]quinazolinones is described. Several of these compounds have exhibited antihypertensive properties in the spontaneously hypertensive rat (SHR). Structure-activity comparisons have indicated that optimal activity is obtained in both the 2-carbethoxydihydroquinazoline series (C) and 2-carbethoxyquinazolinone series (D) when there is either a carbethoxy or cyanoethyl group at position 6 and no substitution in the benzene ring, while optimal activity is obtained in the 2-methyl-quinazolinone series (D) when both position 6 and the benzene ring are unsubstituted.

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