The highly toxic plant alkaloid strychnine is often isolated in the form of the anion salt of its protonated tertiary amine. Here, we characterize the relative influence of different counterions on (1)H and (13)C chemical shifts in several strychnine salts in D2O, methanol-d4 (CD3OD), and chloroform-d (CDCl3) solvents. In organic solvents but not in water, substantial variation in chemical shifts of protons near the tertiary amine was observed among different salts. These secondary shifts reveal differences in the way each anion influences electronic structure within the protonated amine. The distributions of secondary shifts allow salts to be easily distinguished from each other as well as from the free base form. Slight concentration dependence in chemical shifts of some protons near the amine was observed for two salts in CDCl3, but this effect is small compared with the influence of the counterion. Distinct chemical shifts in different salt forms of the same compound may be useful as chemical forensic signatures for source attribution and sample matching of alkaloids such as strychnine and possibly other organic acid and base salts.
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http://dx.doi.org/10.1002/mrc.3945 | DOI Listing |
Dalton Trans
January 2025
P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Leninsky Prospekt 53, 119991 Moscow, Russian Federation.
We synthesized and investigated a new series of Sm 1,3-diketonate complexes with CF-homologous thiophene-containing ligands. A clear correlation was found between the number of fluorine atoms in the 1,3-diketone's carbon chain and the luminescent properties of the samarium(III) complexes. The ligand modification method employed facilitates targeted and significant enhancements in the photoluminescence quantum yield (PLQY).
View Article and Find Full Text PDFJ Nat Prod
January 2025
Department of Pharmacy, University of Salerno, Via Giovanni Paolo II 132, IT-84084 Fisciano, Salerno, Italy.
As a continuation of our pharmacognostic studies on different species growing in Türkiye, the phytochemical investigation of the roots of Hub.-Mor., a licorice species endemic to Türkiye, was carried out.
View Article and Find Full Text PDFBJC Rep
January 2025
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Background: Osteosarcoma is the most common malignant bone tumour with limited treatment options and poor outcomes in advanced metastatic cases. Current immunotherapies show limited efficacy, highlighting the need for novel therapeutic approaches. Systemic immune activation by Toll-like receptor 4 (TLR4) immunostimulants has shown great promise; however, current TLR4 agonists' toxicity hinders this systemic approach in patients with osteosarcoma.
View Article and Find Full Text PDFBMJ Case Rep
January 2025
Ophthalmology, Royal Adelaide Hospital, Adelaide, South Australia, Australia.
Here, we describe a rare case of drug-induced unilateral ciliary body effusion precipitated by topical brinzolamide, presenting acutely with pain, angle closure and myopic shift.Ciliary body effusion was suspected clinically and confirmed by ultrasound biomicroscopy. Brinzolamide was ceased, atropine instilled and the ciliary body effusion promptly resolved without need for further treatment.
View Article and Find Full Text PDFJ Dermatolog Treat
December 2025
Institute for Health Services Research in Dermatology and Nursing (IVDP), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany.
Purpose: Dupilumab is a widely recommended treatment for moderate-to-severe atopic dermatitis (AD), with known ocular side effects but less frequent cutaneous reactions.
Material And Methods: This case report details a 52-year-old female patient with atopic dermatitis treated with dupilumab. After an initially successful treatment, the patient developed a rosacea-like dermatitis.
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