Developing a Diabetes Discharge Order Set for Patients With Diabetes on Insulin.

Background: Insulin, a high-risk medication, is prone to prescribing errors. Patients with diabetes experience higher hospitalization rates and extended hospital stays. Prescription errors, such as missing orders, inappropriate insulin type, missing instructions, and lack of appropriate intensification of insulin regimens are common issues.

Pitfalls in the Optimization of Conformer Populations to Maximize the Similarity between Predicted and Experimental Chiroptical Spectra.

The conformational populations of pantolactone, epichlorohydrin, and -acetyl-tryptophan methyl ester were investigated by using similarity analysis between their calculated and experimental chiroptical spectra. By performing the analysis on pantolactone using two different chiroptical methods, namely, vibrational circular dichroism and Raman optical activity, it was found that the optimal sets of conformers do not match between the two methods, indicating that the conformational populations obtained by optimizing the similarity between calculated and experimental spectra are unlikely to be more accurate than energy-based Boltzmann populations. Also, it was found for pantolactone, epichlorohydrin, and -acetyl-tryptophan methyl ester that the similarity between calculated and experimental spectra would often not vary significantly if each of the populated conformers was discarded, one at a time.

Influence of microsolvation on vibrational circular dichroism spectra in dimethyl sulfoxide solvent: A Bottom-Up approach using Quantum cluster growth.

Chiroptical spectroscopic measurements serve as routine methods to assign the absolute configuration of chiral compounds and interpret their conformational behavior in solution. One common challenge is the use of strongly hydrogen-bonding solvents, which can significantly bias the conformational ensemble and affect the vibrational circular dichroism (VCD) active bands in solution. One such solvent is dimethyl sulfoxide (DMSO)-an excellent solvent for stubborn compounds-that must be explicitly considered in VCD analysis.

Chiral explosives: A theoretical investigation of structure and chiroptical properties of triacetone triperoxide and hexamethylene triperoxide diamine.

Triacetone triperoxide (TATP) and hexamethylene triperoxide diamine (HMTD) are cyclic peroxides that exhibit atropisomerism resulting from restricted rotation around three peroxide bonds. As a result, one pair of enantiomers with D symmetry and another pair of enantiomers with C symmetry can be identified. Previous studies, based on mass spectrometry data and computational results, have shown that conformations of TATP with D and C symmetry can be isolated.

Glycemic Management of Hospitalized Patients Receiving Nutrition Support.

Enteral nutrition (EN) and parenteral nutrition (PN) increase the risk of hyperglycemia and adverse outcomes, including mortality, in patients with and without diabetes. A blood glucose target range of 140-180 mg/dL is recommended for hospitalized patients receiving artificial nutrition. Using a diabetes-specific EN formula, lowering the dextrose content, and using a hypocaloric PN formula have all been shown to prevent hyperglycemia and associated adverse outcomes.

Real-World Performance of the Afirma Genomic Sequencing Classifier (GSC)-A Meta-analysis.

Context: The Afirma® GSC aids in risk stratifying indeterminate thyroid nodule cytology (ITN). The 2018 GSC validation study (VS) reported a sensitivity (SN) of 91%, specificity (SP) of 68%, positive predictive value (PPV) of 47%, and negative predictive value (NPV) of 96%. Since then, 13 independent real-world (RW) postvalidation studies have been published.

Synthesis, characterization and absolute configurations of methyl ladderanoates.

Methyl esters of [5]-ladderanoic acid and [3]-ladderanoic acid were prepared by esterification of the acids isolated from biomass at a wastewater treatment plant. Optical rotations at six different wavelengths (633, 589, 546, 436, 405 and 365 nm) and vibrational circular dichroism (VCD) spectra in the 1800-900 cm region were measured in CDCl solvent and compared with quantum chemical (QC) predictions using B3LYP functional and 6-311++G(2d,2p) basis set with polarizing continuum model representing the solvent. QC predictions gave negative optical rotations at all six wavelengths for (R)-methyl [5]-ladderanoate and positive optical rotations for (R)-methyl [3]-ladderanoate, the same signs as previously reported for the corresponding acids.

Chiroptical spectroscopic studies for the absolute configuration determination of hexahydrocurcumin and octahydrocurcumin.

Hexahydrocurcumin (HHC) and octahydrocurcumin (OHC) were synthesized, and their enantiomers were separated using supercritical fluid chromatography. The absolute configurations (ACs) of HHC and OHC were independently determined using experimental measurements and quantum theoretical predictions of vibrational circular dichroism, electronic circular dichroism, and optical rotatory dispersion. These studies lead to AC assignments of (-)-(R)-HHC and (+)-(R,R)-OHC.

Comparison of Afirma GEC and GSC to Nodules Without Molecular Testing in Cytologically Indeterminate Thyroid Nodules.

Background: Analysis of cytologically indeterminate thyroid nodules with Afirma Gene Expression Classifier (GEC) and Genomic Sequencing Classifier (GSC) can reduce surgical rate and increase malignancy rate of surgically resected indeterminate nodules.

Methods: Retrospective cohort analysis of all adults with cytologically indeterminate thyroid nodules from January 2013 through December 2019. We compared surgical and malignancy rates of those without molecular testing to those with GEC or GSC, analyzed test performance between GEC and GSC, and identified variables associated with molecular testing.

Absolute configuration of a [1]rotaxane determined from vibrational and electronic circular dichroism spectra.

The experimental vibrational circular dichroism (VCD) and electronic circular dichroism (ECD) spectra were measured for the enantiomers of [1]rotaxane 1. These experimental spectra have been analyzed using predicted VCD and ECD spectra for (S, R ) or (S, S ) diastereomers using density functional theory. This comparison allowed for a definitive assignment of the absolute configuration of 1.

Chiral Molecular Structure Determination for a Desired Compound Just from Its Molecular Formula and Vibrational Optical Activity Spectra.

A novel proof-of-concept model for chiral molecular structure determination using just the molecular formula and vibrational optical activity (VOA) spectra is presented. To verify this concept, the molecular formula of a desired compound is used to generate all possible chiral structural isomers and their VOA spectra are predicted. The similarity analyses of predicted VOA spectra were then carried out in two different ways: (a) similarity between VOA spectrum of one structural isomer with those of the rest, referred to as cross-correlations; (b) similarity between VOA spectra of all chiral structural isomers with the experimental VOA spectra of the desired compound.

Absolute configuration of seco-eudesmanolide inuloxin D from experimental and predicted chiroptical studies of its 4-O-acetyl derivative.

Sesquitepenoids inuloxins A-D, belonging to different subgroups, were isolated from Dittrichia viscosa and showed potential biocontrol of some parasitic plants as Pelipanche, Orobanche, and Cuscuta species. The absolute configurations of the first three inuloxins A-C were previously determined by using experimental and computational chiroptical spectroscopic methods. The absolute configuration of inuloxin D remains to be established.

How important are the intermolecular hydrogen bonding interactions in methanol solvent for interpreting the chiroptical properties?

Two crispine A analogs and tetrahydrofuro[2,3-b]furan-3,3a(6aH)-diol, endowed with hydroxyl groups that can participate in intramolecular hydrogen bonding, have been synthesized and experimental vibrational circular dichroism (VCD) spectra and optical rotatory dispersion (ORD) data have been measured in CDOD/CHOH solvents. The absolute configurations (ACs) of these compounds have been determined using their synthetic schemes, supplemented wherever possible with X-ray diffraction data. The ACs are also analyzed with quantum chemical (QC) calculations of VCD and ORD utilizing implicit solvation as well as explicit solvation models, with the later employing classical molecular dynamics (MD) simulations.

Chemical Synthesis of [H]-Ethyl Tosylate and Exploration of Its Crypto-optically Active Character Combining Complementary Spectroscopic Tools.

Small chiral molecules are excellent candidates to push the boundaries of enantiodiscrimination analytical techniques. Here is reported the synthesis of two new deuterated chiral probes, ()- and ()-[H]-ethyl tosylate, obtained with high enantiomeric excesses. Due to their crypto-optically active properties, the discrimination of each enantiomer is challenging.

Optical purity, enantiomeric excess and the Horeau effect.

The optical purity of an enantiomeric mixture deduced from specific rotation measurements was found by Horeau to be different from its enantiomeric excess, which came to be known as the Horeau effect. This observation had important implications in the practical use of specific rotations and has led to investigations on homochiral and heterochiral aggregation processes. In this review, dedicated to the Horeau principle, the theoretical basis for the observance of the Horeau effect and a survey of the specific rotation studies investigating the Horeau effect are provided, and possible future investigations are suggested.

Absolute Configuration and Conformation of (-)---Butylphenylphosphinoamidate: Chiroptical Spectroscopy and X-ray Analysis.

The absolute configuration and conformations of (-)--butylphenylphosphinoamidate were determined using three different chiroptical spectroscopic methods, namely vibrational circular dichroism (VCD), electronic circular dichroism (ECD), and optical rotatory dispersion (ORD). In each of the spectroscopic methods used, experimental data for the (-)-enantiomer of -butylphenylphosphinoamidate were measured in the solution phase. Using the concentration-dependent experimental infrared spectra, the existence of dimers in the solution was investigated, and the monomer-dimer equilibrium constant was determined.

Vibrational optical activity for structural characterization of natural products.

Covering: 2015 to up to 2019 This review presents the recent progress towards elucidating the structures of chiral natural products and applications using vibrational optical activity (VOA) spectroscopy. Vibrational circular dichroism (VCD) and vibrational Raman optical activity (VROA) are two separate branches of VOA spectroscopy, providing independent and complementary structural information. While determining the absolute configuration (AC) of a given natural product is the primary goal, the determination or assessment of major conformations associated with each diastereomer is also a significant part of this enquiry.

Natural Product-Derived Chiral Pyrrolidine-2,5-diones, Their Molecular Structures and Conversion to Pharmacologically Important Skeletons.

The versatility of the natural products (2,3)- and (2,3)-3-hydroxy-5-oxotetrahydrofuran-2,3-dicarboxylic acids ( and ), isolated in large amounts from tropical plant sources, has been demonstrated by the construction of 3-substituted and 3,4-disubstituted chiral pyrrolidine-2,5-diones. The absolute configurations of chiral pyrrolidine-2,5-diones have been ascertained using chiroptical spectroscopic methods and/or single-crystal XRD data. A combination of different reaction strategies delivering a diverse matrix of fused heterocyclic ring systems is presented.

Enhancement of the chiroptical response of α-amino acids via N-substitution for molecular structure determination using vibrational circular dichroism.

The chiroptical response in the form of vibrational circular dichroism (VCD) in the midinfrared region is found to be enhanced when a hydrogen of amino group of l-tryptophan is substituted with acetyl, acryloyl, or maleyl group. The order of preference for VCD enhancement is found to be acryloyl > acetyl > maleyl group. The resulting experimental VCD spectra are also found to be satisfactorily reproduced by the quantum mechanical (QM) predicted spectra.

Dissymmetry Factor Spectral Analysis Can Provide Useful Diastereomer Discrimination: Chiral Molecular Structure of an Analogue of (-)-Crispine A.

(1,10)-1'-(()-1,2-Dihydroxyethyl)-1-hydroxy-8,9-dimethoxy1,5,6,10-tetrahydropyrrolo [2,1-]isoquinolin-3(2)-one, an analogue of (-)-crispine A, with three stereogenic centers is synthesized and its absolute configuration (AC) established using the combined information derived from the synthetic scheme and single crystal X-ray diffraction data. The experimental chiroptical spectra (namely, optical rotatory dispersion (ORD), electronic circular dichroism (ECD), and vibrational circular dichroism (VCD)) and the corresponding quantum chemical (QC) predicted spectra for all diastereomers are used to evaluate the AC. The AC of the synthesized compound could be correctly established using any one of the three chiroptical spectroscopic methods (ORD, ECD, or VCD) when the relative configuration is constrained to be that derived from X-ray data or when the ACs of two of the chiral centers are constrained to be those derived from the synthetic scheme.

Chiral Molecular Structures of Substituted Indans: Ring Puckering, Rotatable Substituents, and Vibrational Circular Dichroism.

The chiral molecular structures of four different substituted indans, namely, ()-1-methylindan, ()-1-methylindan-1-d, ()-1-aminoindan, and ()-1-indanol, were investigated using experimental vibrational absorption and vibrational circular dichroism spectra and corresponding spectra predicted using quantum chemical (QC) calculations. All of these molecules possess two ring puckering conformations, with ring puckering leading to the pseudoequatorial substituent being approximately four times more abundant over that leading to the pseudoaxial substituent. The amino group in 1-aminoindan has three conformations arising from the rotation of NH group, for each ring puckering conformation, resulting in a total of six conformations.

Peyssonnosides A-B, Unusual Diterpene Glycosides with a Sterically Encumbered Cyclopropane Motif: Structure Elucidation Using an Integrated Spectroscopic and Computational Workflow.

Two sulfated diterpene glycosides featuring a highly substituted and sterically encumbered cyclopropane ring have been isolated from the marine red alga Peyssonnelia sp. Combination of a wide array of 2D NMR spectroscopic experiments, in a systematic structure elucidation workflow, revealed that peyssonnosides A-B (1-2) represent a new class of diterpene glycosides with a tetracyclo [7.5.

Absolute Configurations of Naturally Occurring [5]- and [3]-Ladderanoic Acids: Isolation, Chiroptical Spectroscopy, and Crystallography.

We have isolated mixtures of [5]- and [3]-ladderanoic acids 1a and 2a from the biomass of an anammox bioreactor and have separated the acids and their phenacyl esters for the first time by HPLC. The absolute configurations of the naturally occurring acids and their phenacyl esters are assigned as R at the site of side-chain attachment by comparison of experimental specific rotations with corresponding values predicted using quantum chemical (QC) methods. The absolute configurations for 1a and 2a were independently verified by comparison of experimental Raman optical activity spectra with corresponding spectra predicted using QC methods.

(R)-Metacycloprodigiosin-HCl: Chiroptical properties and structure.

(R)-Metacycloprodigiosin can exist in three different tautomeric forms, each with hydrogens at C9' and C12 in syn or anti orientation. With the addition of HCl, this structural diversity reduces to syn-(R)-metacycloprodigiosin-HCl (1a) and anti-(R)-metacycloprodigiosin-HCl (1b), each with multiple conformers. Energetics and chiroptical properties, namely, electronic circular dichroism (ECD) and specific optical rotation (SOR), of (R)-metacycloprodigiosin-HCl have been investigated at B3LYP/6-311++G(2d,2p) level.