2-(Dibutylamino)-3-(4-fluorophenyl)-5,6,7,8-tetrahydro-7-methyl-6,8-diphenylpyridine[3′,4′:2,3]thieno[5,4-d]pyrimidin-4(3H)-one

In the crystal structure of the title compound, C36H39FN4OS, the two fused rings of the thienopyrimidine system are coplanar. The 4-fluorophenyl ring is twisted with respect to the heterocyclic pyrimidinone ring by 67.21 (14)°. The piperidine ring shows a half-chair conformation. One of the n-butyl chains is disordered equally over two sites. The crystal packing is stabilized by C—H⋯O hydrogen bonds.

In the crystal structure of the title compound, C 36 H 39 FN 4 OS, the two fused rings of the thienopyrimidine system are coplanar. The 4-fluorophenyl ring is twisted with respect to the heterocyclic pyrimidinone ring by 67.21 (14) . The piperidine ring shows a half-chair conformation. One of the n-butyl chains is disordered equally over two sites. The crystal packing is stabilized by C-HÁ Á ÁO hydrogen bonds.

Related literature
The preparation and biological activity are described by Walter (1999a,b). For related literature, see: Ding et al. (2004). For the crystal structures of other fused pyrimidinone derivatives, see: Hu et al. (2006Hu et al. ( , 2007.  Table 1 Hydrogen-bond geometry (Å , ). The derivatives of heterocycles containing the thienopyrimidine system, which are well known bioisosteres of quinazolines, are of great importance because of their remarkable biological properties (Walter, 1999a;Walter, 1999b;Ding et al., 2004). Recently, we have focused on the synthesis of the fused heterocycle systems containing thienopyrimidine via aza-Wittig reaction at room temperature. Some X-ray crystal structures of fused pyrimidinone derivatives have been reported (Hu et al., 2006;2007). The title compound ( Fig. 1) may be used as a precursor for obtaining bioactive molecules. The two fused rings of the thienopyrimidine ring system are coplanar, making a dihedral angle of 0.36 (13)°. The p-fluorophenyl ring is twisted with respect to pyrimidinone ring by 67.21 (14)°. The piperidine ring shows a half-chair conformation [φ =25.9 (4)° and θ = 49.9 (3)°, puckering Amplitude = 0.515 (3) Å]. One of the n-butyl chains is disordered over two sites. The crystal packing is stabilized by C-H···O hydrogen bonds interactions (Table 1).

S2. Experimental
To a solution of ethyl 2-((p-flurophenylimino)methyleneamino)-4,5,6,7-tetrahydro-6-methyl-5,7-diphenylthieno[2,3c]pyridine-3-carboxylate (3 mmol) in dichloromethane (5 ml) was added dibutylamine (3 mmol). After stirring the reaction mixture for 1 h, the solvent was removed and anhydrous ethanol (10 ml) with several drops of EtONa in EtOH was added. The mixture was stirred for 4 h at room temperature. The solution was concentrated under reduced pressure and the residue was recrystallized from dichloromethane and ethanol (v/v = 1:1) to give the title compound in a yield of 80%. Crystals suitable for single-crystal X-ray diffraction were obtained by recrystallization from a mixed solvent of ethanol and dichloromethane (1:3 v/v) at room temperature.

S3. Refinement
All H-atoms were positioned with idealized geometry and refined using a riding model with U iso (H)= 1.5U eq (C) for methyl H atoms and U iso (H) =1.2U eq (C) for all other H atoms and with C-H ranging from 0.93° to 0.98 Å. The methyl groups were allowed to rotate but not to tip. Three atoms of one n-butyl chains are disordered over two sites with site occupation factors of 0.540 (12) and 0.460 (12).
Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.