Methyl 4,5-diacet­oxy-1-oxo-2-phenyl­perhydro-4,6-epoxy­cyclo­penta­[c]pyridine-7-carboxyl­ate ethanol solvate

The title compound, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as an ethanol monosolvate, C20H21NO8·C2H6O. The title mol­ecule comprises a fused tricyclic system containing two five-membered rings (cyclo­pentane and tetra­hydro­furan) in the usual envelope conformations and one six-membered ring (piperidinone) adopting a flattened twist–boat conformation

Biomedical applications of sapphire shaped crystals

We have proposed novel medical instrument

Methyl 7,8-diacet­oxy-11-oxo-5-(2-oxo­pyrrolidin-1-yl)-7,9-epoxy­cyclo­penta­[4,5]pyrido[1,2-a]quinoline-10-carboxyl­ate sesquihydrate

The title compound, C26H28N2O9·1.5H2O, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as a sesquihydrate with the O atom of one of the two independent water mol­ecules occupying a special position on a twofold axis. The organic mol­ecule comprises a fused penta­cyclic system containing two five-membered rings (cyclo­pentane and tetra­hydro­furan) and three six-membered rings (piperidinone, tetra­hydro­pyridine and benzene). The five-membered rings have the usual envelope conformations, and the central six-membered piperidinone and tetra­hydro­pyridine rings adopt boat and sofa conformations, respectively. In the crystal, there are three independent O—H⋯O hydrogen bonds, which link the organic mol­ecules and water mol­ecules into complex two-tier layers parallel to (001). The layers are further linked into a three-dimensional framework by attractive inter­molecular carbon­yl–carbonyl inter­actions

(6aS*,6bS*,11R*,11aR*)-6-(2-Furyl­methyl)-5,12-dioxo-5,6,6a,6b,7,11,11a,12-octa­hydro­furo[3′,2′:5,6]isoindolo[2,1-a]quinazoline-11-carb­oxy­lic acid

The title compound, C23H18N2O6, is the product of an intra­molecular thermal cyclo­addition within 1-malein-2-[(E)-2-(2-fur­yl)vin­yl]-4-oxo-3,4-dihydro­quinazoline. The mol­ecule comprises a previously unknown fused penta­cyclic system containing two five-membered rings (2-pyrrolidinone and furan) and three six-membered rings (benzene, 2,3-dihydro-4-pyrimidinone and dihydro­cyclo­hexa­ne). The central five-membered pyrrolidinone ring has the usual envelope conformation. The six-membered dihydro­pyrimidinone and dihydro­cyclo­hexane rings adopt a half-boat and a half-chair conformation, respectively. The dihedral angle between the planes of the terminal benzene and furan rings is 45.99 (7)°. In the crystal, O—H⋯O hydrogen bonds link the mol­ecules into centrosymmetric dimers. Weak C—H⋯O hydrogen bonds consolidate further the crystal packing, which exhibits π–π inter­actions, with a short distance of 3.556 (3) Å between the centroids of benzene rings of neighbouring mol­ecules

In vitro terahertz spectroscopy of gelatin-embedded human brain tumors - a pilot study

We have performed the in vitro terahertz (THz) spectroscopy of human brain tumors. In order to x tissue

Sapphire-based medical instruments for diagnosis, surgery and therapy

In this work, we present a brief overview of sapphire medical instruments. Sapphire demonstrates a unique combination of physical properties, such as high hardness and chemical inertness, biocompatibility and high thermal conductivity, high transparency in a wide spectral range that makes it suitable for various medical applications. We demonstrate the examples of scalpel, capillary needle for laser therapy, neuroprobe and applicator for cryosurgery. Each of them combines different modalities in one instrument. Among them are tissue resection, therapy via electromagnetic wave delivering, aspiration, diagnosis, and tissue freezing. Sapphire instruments can be accompanied with magnetic resonance imaging and allow multiple sterilization