Cyclic compounds synthesized from histamine (Hi) or histidine (His) with pyridoxal (PL)--[Hi-PL, His-PL] and Hi or His with pyridoxal 5'-phosphate (PLP)--[Hi-PLP, His-PLP] were tested for stability in buffer, acid and base solutions, crude homogenates of various tissues and in the presence of enzymes which metabolize Hi or His. The cyclic pyridoxal compounds were stable in all experimental conditions, whereas phosphopyridoxal cyclic products were degraded by rat intestinal DAO and rat intestine homogenate, apparently enzymatically. In acidic and basic solutions changes in migration velocity and u.v. absorption spectrum occur. The characteristic fluorescence of these cyclic compounds is described.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/BF02111431 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Rational Design of Porous Organic Framework (POF) for Efficient Conversion of CO2 to Cyclic Carbonates and 2-Oxazolidinones at Atmospheric Pressure Conditions.
Chem Asian J
January 2025
Indian Institute of Technology Ropar, Chemistry, Nangal Road, 140001, Rupnagar, INDIA.
Carbon dioxide (CO2) capture and its subsequent catalytic fixation into usable compounds represent a potential approach for addressing the energy problem and the implications of global warming. Hence, it is necessary to develop effective catalytic systems required for the transformation of CO2 into valuable chemicals/fuels. Herein, we rationally designed a hydroxyl-functionalized porous organic framework (OH-POF) consisting of both acidic (OH) as well as basic N sites for the transformation of CO2 using epoxides for the production of cyclic carbonates (CCs), a useful commodity chemical under environmental-friendly, metal/solvent/co-catalyst-free conditions.
View Article and Find Full Text PDFDichlorination of olefins with trichloroisocyanuric acid (TCCA) and tetrabutylammonium chloride (TBACl).
Org Biomol Chem
January 2025
Department of Chemistry, Faculty of Arts and Sciences, Amasya University, Amasya, Turkey.
Herein, a new metal-free, molecular chlorine-free, environmentally friendly, atom-economical, short time, inexpensive and simple operation method with mild reaction conditions for chlorination of alkenes, cyclic alkenes, ,-unsaturated carbonyl compounds, heteroaromatics, and natural products was reported with up to 96% yields using trichloroisocyanuric acid (TCCA) as the electrophilic chlorine source and TBACl as the nucleophilic chlorine source. It was demonstrated with bicyclic alkene benzonorbornadiene that regioselective chlorobromination and dibromination reactions can be carried out through TCCA/TBABr redox reactions, where TCCA acts as an oxidant in the presence of TBABr. The structures of the redox products were confirmed as a result of control experiments conducted with the newly presented DBI/TBACl and DBI/TBABr halogenation pairs.
View Article and Find Full Text PDFRecent transformations of vinylidene cyclopropanes (VDCPs).
Chem Commun (Camb)
January 2025
Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
Methodological studies on the transformations of vinylidene cyclopropanes (VDCPs) have been substantially developed in the past few decades, and significant progress has been achieved in visible light-mediated, non-metal-related, and transition metal-catalyzed processes. In particular, when reactive functional groups are introduced into the backbone of VDCPs, a variety of cascade or sequential transformations can take place to produce more complex cyclic or polycyclic compounds. This review describes the recent advancements in this field.
View Article and Find Full Text PDFThymol and Carvacrol as Potential Tocolytic and Anti-inflammatory Agents in Pregnant Rat Uterus.
Curr Mol Pharmacol
January 2025
Área Académica de Medicina del Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo, Pachuca, Hidalgo, México.
Introduction: This work aimed to evaluate the anti-inflammatory and myorelaxant effect of thymol (TM) and carvacrol (CAR) in the pregnant rat uterus. Both compounds exhibit considerable antimicrobial, antispasmodic, and anti-inflammatory effects and due to these properties, they were studied in this in vitro model of premature birth induced by infection.
Method: All uterine tissues were studied in uterine contraction tests to determine the inhibitory effect of TM, CAR (10, 56, 100, 150, and 230 μM), and nifedipine (a calcium channel antagonist) on phasic and tonic contraction induced by electro- and pharmacomechanical stimuli.
Biosynthesis of lactacystin as a proteasome inhibitor.
Commun Chem
January 2025
Graduate School of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, Hokkaido, 060-8628, Japan.
Lactacystin is an irreversible proteasome inhibitor isolated from Streptomyces lactacystinicus. Despite its importance for its biological activity, the biosynthesis of lactacystin remains unknown. In this study, we identified the lactacystin biosynthetic gene cluster by gene disruption and heterologous expression experiments.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!