6β,15β-Diacet­oxy-1β,7β,13α-trihydr­oxy-7α,20-ep­oxy-ent-kaur-16-ene

The title compound, C24H34O8, a natural ent-kaurane diterpenoid, is composed of four rings with the expected cis and trans junctions. The crystal structure is stabilized by inter­molecular O—H⋯O hydrogen bonds. In addition, an intra­molecular O—H⋯O hydrogen bond occurs

1α,11α,15β-Triacet­oxy-7β-hydroxy-7α,20-ep­oxy-ent-kaur-16-en-6-one

The title compound, C26H34O9, a natural ent-kaurane diterpenoid, is composed of four rings with the expected cis and trans junctions. In the crystal structure, the mol­ecules stack along the a axis and are linked together by inter­molecular O—H⋯O hydrogen bonds

Experimentally obtaining the Likeness of Two Unknown Quantum States on an NMR Quantum Information Processor

Recently quantum states discrimination has been frequently studied. In this paper we study them from the other way round, the likeness of two quantum states. The fidelity is used to describe the likeness of two quantum states. Then we presented a scheme to obtain the fidelity of two unknown qubits directly from the integral area of the spectra of the assistant qubit(spin) on an NMR Quantum Information Processor. Finally we demonstrated the scheme on a three-qubit quantum information processor. The experimental data are consistent with the theoretical expectation with an average error of 0.05, which confirms the scheme.Comment: 3 pages, 4 figure

1α,6β,7β,14β,15β-Penta­hydr­oxy-7α,20-ep­oxy-ent-kaur-16-ene

The title compound, enmenol, C20H30O6, a natural ent-kaurane diterpenoid, comprises five fused rings, four of which are six-membered. Cyclo­hexane ring A adopts a chair conformation, rings B and C adopt boat conformations, while ring D has an envelope conformation, and two intramolecular O—H⋯O interactions occur. In the crystal, inter­molecular O—H⋯O hydrogen bonds generate a two dimensional network

6β-Acet­oxy-1α,7β,11β,15β-tetra­hydr­oxy-7α,20-ep­oxy-ent-kaur-16-ene

The title compound, C22H32O7, a natural ent-kaurane diterpenoid also referred to as Maoyecrystal F, was obtained from the medicinal plant Isodon nervosa. There are four rings with the expected cis and trans junctions. Cyclohexane ring A adopts a chair conformation, rings B and C adopt boat conformations, while the five-membered ring has an envelope conformation. The mol­ecules stack along the a axis in the crystal and are linked together by inter­molecular O—H⋯O hydrogen bonds

15α,20β-Dihydr­oxy-6β-meth­oxy-6,7-seco-6,20-ep­oxy-1,7-olide-ent-kaur-16-ene

The title compound, C21H30O6, a natural ent-kaurane diterpenoid, was obtained from the medicinal plant Isodon serra. The five rings in the mol­ecule exhibit the expected cis and trans junctions. The three six-membered rings adopt chair, twist-boat and boat conformations, while two five-membered rings adopt envelope conformations. There are two mol­ecules in the asymmetric unit, related by a non-crystallographic twofold screw axis; the main difference is in the different degrees of distortion of ring B. In the crystal, the mol­ecules are linked by inter­molecular O—H⋯O hydrogen bonds, forming chains along the b axis

GPS-MBA: Computational Analysis of MHC Class II Epitopes in Type 1 Diabetes

As a severe chronic metabolic disease and autoimmune disorder, type 1 diabetes (T1D) affects millions of people world-wide. Recent advances in antigen-based immunotherapy have provided a great opportunity for further treating T1D with a high degree of selectivity. It is reported that MHC class II I-Ag7 in the non-obese diabetic (NOD) mouse and human HLA-DQ8 are strongly linked to susceptibility to T1D. Thus, the identification of new I-Ag7 and HLA-DQ8 epitopes would be of great help to further experimental and biomedical manipulation efforts. In this study, a novel GPS-MBA (MHC Binding Analyzer) software package was developed for the prediction of I-Ag7 and HLA-DQ8 epitopes. Using experimentally identified epitopes as the training data sets, a previously developed GPS (Group-based Prediction System) algorithm was adopted and improved. By extensive evaluation and comparison, the GPS-MBA performance was found to be much better than other tools of this type. With this powerful tool, we predicted a number of potentially new I-Ag7 and HLA-DQ8 epitopes. Furthermore, we designed a T1D epitope database (TEDB) for all of the experimentally identified and predicted T1D-associated epitopes. Taken together, this computational prediction result and analysis provides a starting point for further experimental considerations, and GPS-MBA is demonstrated to be a useful tool for generating starting information for experimentalists. The GPS-MBA is freely accessible for academic researchers at: http://mba.biocuckoo.org