Hi, forgot to mention, that if in GChemPaint the structure is drawn using bond symbols that indicate stereochemistry (I mean the "bond pointing upwards" and "bond pointing downwards" symbols) you could try modifying the Z-coordinates of the corresponding atoms accordingly ; say the Z-coordinate of the atom which is "upper" is added a bit and Z-coordinate of the atom which is "lower" is subtracted a bit. The unit of distance used in ghemical is nanometer ; 1 =C5 =3D 0.1 nm. So a first guess could be that atom being "upper" means +0.1 change in Z and atom being "lower" means -0.1 change in Z. Regards, =09Tommi