1,4-Dihydrobenzo[g]quinoxaline-2,3-dione

14-23 Singh

About 20 years have elapsed since those studies were done. During this period, many changes that might influence teenage reproductive behavior and how it is viewed have taken place within the industrialized world. The proportion of births to unmarried women has risen,2 and nonmarital childbearing is more acceptable, both among adolescents and among women older than 20. Access to contraception a...

White Paper 23 - 14 Ancestry Timeline

شناسنامه علمی، دوره 14، شماره1 - شماره پیاپی 23، بهار 1385

14-Methoxy-2,16-dioxapentacyclo[7.7.5.01,21.03,8.010,15]henicosa-3(8),10,12,14-tetraene-7,20-dione

The title compound, C(20)H(20)O(5), was synthesized from the reaction between 3-methoxysalicaldehyde and 1,3-cyclo-hexa-nedione in the presence of palladium(II) chloride. The two fused xanthene rings and one of the six-membered cyclo-hexane rings adopt envelope conformations, while the other six-membered cyclo-hexane ring is in a chair conformation. The mol-ecular packing is stabilized by weak ...

14-Hy­droxy-8,14-secogammacera-7-ene-3,21-dione from the bark of Lansium domesticum Corr.

In the title compound (kokosanolide B), C(30)H(48)O(3), the hexa-hydro- and octa-hydro-naphthalen-2-one ring systems are connected through an ethyl-ene fragment, with a C-CH(2)-CH(2)-C torsion angle of 176.2 (2)°. The cyclo-hexene ring adopts a half-chair conformation, while the other six-membered rings adopt distorted chair conformations. In the crystal, adjacent mol-ecules are linked into a z...