In the title compound, C(25)H(23)N(3)O(3)S, an intra-molecular N-H⋯O inter-action generates an S(6) ring, which stabilizes the enamine-keto form of the compound. This S(6) ring and the pyrazole ring are essentially coplanar, making a dihedral angle of 1.49 (6)°. The bond lengths within the S(6) ring of the mol-ecule lie between classical single- and double-bond lengths, indicating extensive con...

In the title mol-ecule, C(20)H(18)BrFN(2)O(2)S, the pyrimidine ring adopts a flattened envelope conformation. The halogenated benzene ring is orthogonal to the planar part of the pyrimidine ring [dihedral angle = 89.05 (4)°], while the other phenyl ring is oriented at an angle of 85.14 (5)°. The ethoxy group is disordered over two orientations with site occpancies of ca 0.869 (4) and 0.131 (4)....

In the title compound, C(11)H(11)FN(4)S, the dihedral angle between the 1,2,4-triazole ring and the benzene ring is 25.04 (12)° and an intra-moleuclar C-H⋯S inter-action leads to an S(6) ring. In the crystal, inversion dimers linked by pairs of N-H⋯S hydrogen bonds generate R(2) (2)(8) loops.

and we call A the zero ring denoted by 0. A ring homomorphism is a mapping f of a ring A into a ring B such that for all x, y ∈ A, f(x + y) = f(x) + f(y), f(xy) = f(x)f(y) and f(1) = 1. The usual properties of ring homomorphisms can be proven from these facts. A subset S of A is a subring of A if S is closed under addition and multiplication and contains the identity element of A. The identity ...

In the title compound, C(16)H(14)N(4)O(2)S, intra-molecular N-H⋯N hydrogen bonding forms an S(5) ring, whereas N-H⋯O and C-H⋯S inter-actions complete S(6) ring motifs. In the crystal, mol-ecules form inversion dimers due to N-H⋯O inter-actions. The dimers are inter-linked through N-H⋯S hydrogen bonds and π-π inter-actions occur with a centroid-centroid distance of 3.8422 (11) Å between the meth...