Abstract: A waveguide coupler includes a first waveguide layer including a first waveguide, a second waveguide layer including a second waveguide optically coupled to the first waveguide, and a dielectric layer between the first waveguide layer and the second waveguide layer in a first direction (e.g., vertical direction). A distance between the first waveguide and second waveguide in a second direction (e.g., a horizontal direction) that is perpendicular to the first direction is greater than zero, and has different values at two or more different sections of the waveguide coupler along a third direction (e.g., the light propagation direction).

Abstract: The compounds (I) are useful as intermediates in the synthesis of hexahydroareno(e)cyclopropa(c)indol-4-ones with antitumoral activity.

Abstract: The areno[e]indols have the formula (I). The methods comprises: (a) reacting (VI) with an aldehyde Ar"--CHO to obtain (VII); (b) oxidizing (VII) to yield the cetone (VIII); (c) reating (VIII) with a strong base and thereafter with an acycle chloride ClCOR, to produce (IX); (d) subjecting to a photochemical cyclization (IX) to produce (I). In said formulas Ar is phenyl or substituted phenyl; Ar' is radical (i) or (ii); R is an acyle group, Ar" is a phenyl, pyrolyl, furanyl or thiophenyl group substituted up to three times by any of the radials R, R.sup.1, R.sup.2, or R.sup.3. The compounds (I) are useful as intermediates in the synthesis of hexahydroareno(e)cyclopropa(c)indol-4-ones with antitumoral activity.