The reactions of 2-perfluoroacyl-1H-benzo[f]chromenes and 6,7-dimethyl-3-trifluoroacetyl-4H-chromene with primary aliphatic amines ammonia afforded a series enamino ketones containing (2-hydroxynaphthalen-1-yl)methyl or 2-hydroxybenzyl substituent in the ?-position respect to carbonyl group. These involved opening pyran ring, which followed aza-Michael addition as initial step. obtained were fo...

Administration of precocene II (6,7-dimethoxy-2, 2-dimethyl chromene) to freshly emerged virgin female flies of S. ruficornis adversely affected the development and differentiation of ovarian follicles leading to a number of morphological abnormalities. Precocene treatment resulted into suppression of development of egg chamber, differentiation of follicular epithelium, degeneration of nurse ce...

The crystal structures of the title compounds, C19H19NO and C31H34N2O, were determined as part of an experiment in an undergraduate teaching laboratory that demonstrates the relationship between mol-ecular structure and function. 1',3',3'-Tri-methyl-spiro-[chromene-2,2'-indoline] is both a photoswitch and thermochromic mol-ecule. Students synthesized it and a bis-indoline adduct and compared th...

One of the important Multi-component reaction (MCRs) is the synthesis of dihydropyrano chromene derivatives by one-pot reaction. In this research, an inexpensive and effective one pot three component procedure with good yields for the synthesis of dihydro pyrano chromenes is reported. In this method, the synthesis of pyrano chromene derivatives was followed by using 4-hydroxycoumarin, malononit...

an efficient and green method for the synthesis of pyrano[3,2-c]chromene or pyrano[4,3-b]pyrone derivatives is described by using a three-component condensation process of malononitrile, aldehyde, and 4-hydroxycoumarine or 4-hydroxypyrone in [bmim]bf4-licl as an ionic liquid.

In the biologically active title compound, C26H26O5, the pyran ring of the chromene unit adopts a half-chair conformation. The C=C double bond of the propenone unit exhibits a trans conformation and the carbonyl group is syn conformation to the double bond. The dihedral angle between the benzene ring and the benzopyran-one moiety is 31.54 (4)°. The mol-ecular structure is stabilized by an intra...