The title compound, C20H28O3, known as 'trichodermaerin' [systematic name: (4E)-4,9,15,16,16-penta-methyl-6-oxa-tetra-cyclo-[10.3.1.0(1,10).0(5,9)]hexa-dec-4-ene-7,13-dione], is a diterpene lactone which was isolated from Trichoderma asperellum. The structure has a tetra-cycic 6-5-7-5 ring system, with the cyclo-hexa-none ring adopting a twisted half-chair conformation and the cyclo-pentane rin...

User stories are a widespread instrument for representing requirements. They describe small user-oriented parts of the system and guide the daily work of developers. Often however, user stories are too coarse, so that misunderstandings or dependencies remain unforeseeable. Granularity of user stories needs to be investigated more, but at the same time is a hard-to-grasp concept. This paper inve...

The asymmetric unit of the title N-heterocyclic carbene compound, C(22)H(32)N(4) (2+)·2PF(6) (-), consists of one half of the N-heterocyclic carbene dication and one hexa-fluoro-phosphate anion. The dication lies across a crystallographic inversion center. The imidazole ring is twisted away from the central benzene ring, making a dihedral angle of 76.23 (6)°. The hexa-fluoro-phosphate anions li...

The title compound, (C(8)H(20)N)[Tb(C(5)HF(6)O(2))(4)], is a tetrakis β-diketonate complex of hexa-fluoro-acetyl-acetone with terbium(III), and tetra-ethyl-ammonium as the counter-ion. This compound shows typical green terbium(III) luminescence upon excitation at about 335 nm. The coordination geometry around the Tb(III) atom is a slightly distorted square anti-prism. One hexa-fluoro-acetyl-ace...

In the title compound, [Cu(C(34)H(24)N(4)O(2)S(2))] or [Cu(bqdapte)], where H(2)bqdapte is 1,2-{bis-[2-(quinoline-2-carboxamido)-phen-yl]sulfan-yl}ethane, the Cu(II) ion is coordinated to the dianionic hexa-dentate bqdapte(2-) ligand by two amide and two quinoline N atoms and two thio-ether S atoms. In the observed conformation of the hexa-dentate ligand, the quinoline rings attain positions re...

I report on special features of a course on statistics and probabilities at my university, where future teachers of mathematics in primary school are instructed on en-active representations of statistical situations and on their analogue modelling. I also report on empirical work with future mathematics teachers of primary school in Baden Württemberg who have been instructed to introduce simple...

The title compound, C(18)H(22)O(6), was obtained by the domino oxa-Michael-aldol (DOMA) reaction and has the cyclo-hexa-none ring in a chair conformation with intra-annular torsion angles in the range 49.9 (2)-58.9 (2)°. The two eth-oxy-carbonyl substituents on the cyclo-hexa-none ring adopt a syn configurations. In the crystal, the mol-ecules self-assemble through duplex inter-molecular hy-dro...

A new organic-inorganic hybrid compound, penta-morpholinium hexa-hydrogen hexa-molybdoferrate(III) sulfate 3.5-hydrate, (C4H10NO)5[Fe(III)(OH)6Mo6O18](SO4)·3.5H2O, was obtained from an aqueous solution. The polyoxidomolybdate (POM) anion is of the Anderson β-type with a central Fe(III) ion. Three of five crystallographically independent morpholinium cations are disordered over two sets of sites...