The N–N bond as a chiral axis: 3-diacylaminoquinazolinones as chiral acylating agents
摘要:
3-Diacylaminoquinazolinones 10 and 15 have high enough barriers to rotation around their N-N bonds to allow separation of each into diastereoisomers. Interconversion of diastereoisomers 10a and 10b occurs on heating in boiling toluene and thermodynamic parameters for this process have been measured, The barriers to rotation around the N-N bonds in analogous monoacylaminoquinazolinones are not sufficient to permit isolation of stereoisomers at room temperature unless the exocyclic nitrogen is additionally substituted e.g. by an alkyl group as in 28, X-Ray crystal structure determinations carried out on 10a, 10b, 15a and 28b confirm the presence of chiral axes, Reaction of both diastereoisomers 15a and 15b with 1-phenylethylamine takes place with exclusive reaction at the 1-acetoxypropionyl carbonyl group and with partial kinetic resolution: the preferred sense of enantioselectivity obtained is dominated by the N-N axis.
A medicament having an inhibitory activity against hematopoietic prostaglandin D2 synthase, which comprises as an active ingredient a compound represented by the following general formula (I) or a salt thereof:
wherein X represents a group represented by the formula —N═C(R
5
)— or the formula —NH—CH(R
5
)—, R
1
, R
2
, R
3
, and R
4
represent a hydrogen atom, a halogen atom, a C
1
to C
6
alkyl group, or a hydroxy group, R
5
represents a C
1
to C
6
alkyl group or a C
6
to C
10
aryl group, and R represents an amino group.
Synthesis of unsymmetrical 3,3′-biquinazoline-2,2′-diones by condensation of 3-aminoquinazolinones with benzoxazinones; fortuitous discovery, and further syntheses of 4-H-3-oxo-1,9a,10-triazaanthracen-9-ones
作者:Michael P. Coogan、Li-ling Ooi、Fabrizio Pertusati
DOI:10.1039/b419108k
日期:——
2' disubstituted 3,3' biquinazoline-4,4'-diones. The reaction is tolerant to a range of heteroatom and unsaturated functionality in the quinazolinone 2-position. However, treatment of 3-amino-2-hydroxymethyl-3H-quinazolin-4-ones with benz[1,3]oxazinone at high temperatures gave 4H-3-oxo-1,9a,10-triazaanthracen-9-ones, an unreported fused heterocyclic system, a more direct synthesis of which, replacing