Psychoactive Plant Database - Neuroactive Phytochemical Collection

1. ACS Catal. 2024 Oct 9;14(20):15713-15720. doi: 10.1021/acscatal.4c04676. 
eCollection 2024 Oct 18.

Asymmetric Monoreduction of α,β-Dicarbonyls to α-Hydroxy Carbonyls by Ene 
Reductases.

Wolder AE(1), Heckmann CM(1), Hagedoorn PL(1), Opperman DJ(2), Paul CE(1).

Author information:
(1)Biocatalysis section, Department of Biotechnology, Delft University of 
Technology, van der Maasweg 9, Delft 2629 HZ, the Netherlands.
(2)Department of Microbiology and Biochemistry, University of the Free State, 
Bloemfontein 9300, South Africa.

Ene reductases (EREDs) catalyze asymmetric reduction with exquisite chemo-, 
stereo-, and regioselectivity. Recent discoveries led to unlocking other types 
of reactivities toward oxime reduction and reductive C-C bond formation. 
Exploring nontypical reactions can further expand the biocatalytic 
knowledgebase, and evidence alludes to yet another variant reaction where flavin 
mononucleotide (FMN)-bound ERs from the old yellow enzyme family (OYE) have 
unconventional activity with α,β-dicarbonyl substrates. In this study, we 
demonstrate the nonconventional stereoselective monoreduction of α,β-dicarbonyl 
to the corresponding chiral hydroxycarbonyl, which are valuable building blocks 
for asymmetric synthesis. We explored ten α,β-dicarbonyl aliphatic, cyclic, or 
aromatic compounds and tested their reduction with five OYEs and one 
nonflavin-dependent double bond reductase (DBR). Only GluER reduced aliphatic 
α,β-dicarbonyls, with up to 19% conversion of 2,3-hexanedione to 
2-hydroxyhexan-3-one with an R-selectivity of 83% ee. The best substrate was the 
aromatic α,β-dicarbonyl 1-phenyl-1,2-propanedione, with 91% conversion to 
phenylacetylcarbinol using OYE3 with R-selectivity >99.9% ee. Michaelis-Menten 
kinetics for 1-phenyl-1,2-propanedione with OYE3 gave a turnover k cat of 0.71 ± 
0.03 s-1 and a K m of 2.46 ± 0.25 mM. Twenty-four EREDs from multiple classes of 
OYEs and DBRs were further screened on 1-phenyl-1,2-propanedione, showing that 
class II OYEs (OYE3-like) have the best overall selectivity and conversion. EPR 
studies detected no radical signal, whereas NMR studies with deuterium labeling 
indicate proton incorporation at the benzylic carbonyl carbon from the solvent 
and not the FMN hydride. A crystal structure of OYE2 with 1.5 Å resolution was 
obtained, and docking studies showed a productive pose with the substrate.

© 2024 The Authors. Published by American Chemical Society.

DOI: 10.1021/acscatal.4c04676
PMCID: PMC11494505
PMID: 39444529

Conflict of interest statement: The authors declare no competing financial 
interest.


2. Int J Mol Sci. 2023 Mar 14;24(6):5573. doi: 10.3390/ijms24065573.

Evaluation of the Selected Mechanical and Aesthetic Properties of Experimental 
Resin Dental Composites Containing 1-phenyl-1,2 Propanedione or 
Phenylbis(2,4,6-trimethylbenzoyl)-phosphine Oxide as a Photoinitiator.

Kowalska-Kuczyńska A(1), Sokołowski J(1), Szynkowska-Jóźwik MI(2), Gozdek T(3), 
Klajn K(3), Kopacz K(4)(5), Bociong K(1).

Author information:
(1)Department of General Dentistry, Medical University of Lodz, 92-213 Lodz, 
Poland.
(2)Faculty of Chemistry, Institute of General and Ecological Chemistry, Lodz 
University of Technology, Zeromskiego 116, 90-543 Lodz, Poland.
(3)Institute of Polymer & Dye Technology, Lodz University of Technology, 
Stefanowskiego 12/16, 90-924 Lodz, Poland.
(4)"DynamoLab" Academic Laboratory of Movement and Human Physical Performance, 
Medical University of Lodz, Pomorska 251, 92-215 Lodz, Poland.
(5)Department of Health Sciences, Medical University of Mazovia, Rydygiera 8, 
01-793 Warszawa, Poland.

The goal of this study was to compare the mechanical properties of experimental 
resin dental composites containing a conventional photoinitiating system 
(camphorquinone CQ and 2-(dimethylami-no)ethyl methacrylate (DMAEMA)) to a 
photoinitiator system containing 1-phenyl-1,2 propanedione (PPD) with 
2-(dimethylami-no)ethyl methacrylate) or acting alone 
phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide (BAPO). The manually produced 
composites consisted of an organic matrix: bis-GMA (60 wt. %), TEGDMA (40 wt. 
%), and silanized silica filler (45 wt. %). The composites contained 0.4/0.8 wt. 
%, 0.8/1.6 wt. %, and 1/2 wt. % of PPD/DMAEMA and another group included 0.25, 
0.5, or 1 wt. % of BAPO. Vickers hardness, microhardness (in the nanoindentation 
test), diametral tensile strength, and flexural strength were assessed, and CIE 
L* a* b* colorimetric analysis was conducted for each composite produced. The 
highest average Vickers hardness values were obtained for the composite 
containing 1 wt. % BAPO (43.73 ± 3.52 HV). There was no statistical difference 
in the results of diametral tensile strength for the experimental composites 
tested. The results of 3-point bending tests were the highest for composites 
containing CQ (77.3 ± 8.84 MPa). Despite the higher hardness of experimental 
composites including PPD or BAPO, compared with composites with CQ, the overall 
results indicate that the composite with CQ still represents a better solution 
when used as a photoinitiator system. Moreover, the composites containing PPD 
and DMAEMA are not promising in terms of color or mechanical properties, 
especially as they require significantly longer irradiation times.

DOI: 10.3390/ijms24065573
PMCID: PMC10053791
PMID: 36982646 [Indexed for MEDLINE]

Conflict of interest statement: The authors declare no conflicts of interest.


3. Ind Eng Chem Res. 2022 Apr 25;61(17):6052-6056. doi: 10.1021/acs.iecr.1c04375.
 eCollection 2022 May 4.

A Simplified Kinetic Model for the Enantioselective Hydrogenation of 
1-Phenyl-1,2-Propanedione over Ir/TiO(2) in the Presence of a Chiral Additive.

Melián-Cabrera I(1), Marzialetti T(2), D'Angelo MFN(3)(4), Campos CH(5), Reyes 
P(5).

Author information:
(1)Applied Photochemistry and Materials for Energy Group, University of La 
Laguna, Avda. Astrofísico Francisco Sánchez, s/n, P.O. Box 456, 38200 San 
Cristóbal de La Laguna, S/C de Tenerife, Spain.
(2)Chemical Engineering Department, School of Engineering, Universidad de 
Concepción, Edmundo Larenas 219, Concepción 4070409, Chile.
(3)Laboratory of Chemical Reactor Engineering, Department of Chemical 
Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 
5600 MB, Eindhoven, The Netherlands.
(4)Sustainable Process Engineering, Department of Chemical Engineering and 
Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, 
The Netherlands.
(5)Departamento de Físico-Química, Facultad de Ciencias Químicas, Universidad de 
Concepción, Edmundo Larenas 129, 4070371, Concepción, Chile.

Comment in
    doi: 10.1021/10.1021/acs.iecr.1c04504.

This communication proposes a preliminary simplified kinetic model for the 
hydrogenation of 1-phenyl-1,2-propanedione that can render up to eight 
compounds, involving regioselectivity and enantioselectivity. The catalytic 
system comprises two functionalities; the heterogeneous catalyst (Ir/TiO2) plays 
the role for the hydrogenation, whereas the adsorption/binding to the active 
site is played by a chiral molecule (cinchonidine), added to the reaction 
mixture. The reaction occurs at room temperature and total pressure of 40 bar. 
The product distribution shows competitive parallel and series pathways with up 
to 12 possible reactions. Despite the complexity of both reaction and catalyst 
system, a simplified kinetic model was able to predict the concentrations 
profiles. The model assumes the reactions to be apparent first order in the 
concentrations of reactant and intermediate products, while the kinetic 
constants include all other effects (partial pressure of hydrogen, solvent and 
catalyst effects, and the concentration of the chiral additive). The 
concentration profiles were well-modeled with low residual values. The errors in 
the kinetic constants (k-values) were small for all relevant parameters of the 
main reaction pathways. Two k-values are nil, which is the lower bound imposed 
in the model, suggesting that these reaction pathways are likely negligible. The 
positive outcome from this simplified model suggests that the process can be 
formally treated as a first-order irreversible homogeneous catalyzed reaction, 
despite a heterogeneous catalyst was employed (with a modifier). Despite the 
promising results, the model must be extended for a more general applicability, 
or conditions where it is applicable.

© 2022 American Chemical Society.

DOI: 10.1021/acs.iecr.1c04375
PMCID: PMC10394662
PMID: 37538052

Conflict of interest statement: The authors declare no competing financial 
interest.


4. Polymers (Basel). 2021 Feb 2;13(3):470. doi: 10.3390/polym13030470.

The Photoinitiators Used in Resin Based Dental Composite-A Review and Future 
Perspectives.

Kowalska A(1), Sokolowski J(1), Bociong K(1).

Author information:
(1)Department of General Dentistry, Medical University of Lodz, 92-213 Lodz, 
Poland.

The presented paper concerns current knowledge of commercial and alternative 
photoinitiator systems used in dentistry. It discusses alternative and 
commercial photoinitiators and focuses on mechanisms of polymerization process, 
in vitro measurement methods and factors influencing the degree of conversion 
and hardness of dental resins. PubMed, Academia.edu, Google Scholar, Elsevier, 
ResearchGate and Mendeley, analysis from 1985 to 2020 were searched 
electronically with appropriate keywords. Over 60 articles were chosen based on 
relevance to this review. Dental light-cured composites are the most common 
filling used in dentistry, but every photoinitiator system requires proper 
light-curing system with suitable spectrum of light. Alternation of 
photoinitiator might cause changing the values of biomechanical properties such 
as: degree of conversion, hardness, biocompatibility. This review contains 
comparison of biomechanical properties of dental composites including different 
photosensitizers among other: camphorquinone, phenanthrenequinone, benzophenone 
and 1-phenyl-1,2 propanedione, trimethylbenzoyl-diphenylphosphine oxide, benzoyl 
peroxide. The major aim of this article was to point out alternative 
photoinitiators which would compensate the disadvantages of camphorquinone such 
as: yellow staining or poor biocompatibility and also would have mechanical 
properties as satisfactory as camphorquinone. Research showed there is not an 
adequate photoinitiator which can be as sufficient as camphorquinone (CQ), but 
alternative photosensitizers like: benzoyl germanium or novel acylphosphine 
oxide photoinitiators used synergistically with CQ are able to improve aesthetic 
properties and degree of conversion of dental resin.

DOI: 10.3390/polym13030470
PMCID: PMC7867280
PMID: 33540697

Conflict of interest statement: The authors declare no conflict of interest.


5. Dent Mater J. 2021 Mar 31;40(2):519-524. doi: 10.4012/dmj.2020-068. Epub 2020 
Dec 24.

Effect of pre-coating with methyl methacrylate containing UV photoinitiators on 
the bond strength of poly(ether ether ketone).

Okawa S(1), Aoyagi Y(2), Kimura T(2), Izumi K(1).

Author information:
(1)Division of Biomimetics, Faculty of Dentistry & Graduate School of Medical 
and Dental sciences, Niigata University.
(2)Division of Bio-Prosthodontics, Faculty of Dentistry & Graduate School of 
Medical and Dental sciences, Niigata University.

This study investigates the effect of pre-coating with methyl methacrylate (MMA) 
containing ultraviolet (UV) photoinitiators on the bond strength of poly(ether 
ether ketone) (PEEK). Cylindrical PEEK blocks were irradiated with 365 nm UV 
light for 5-20 s after they were coated with MMA containing 0.4-3.0 wt% UV 
photoinitiators: [1-phenyl-1,2-propanedione (PPD)], 
[diphenyl(2,4,6-trimethylbenzoyl) (TMDPO)], and [phenyl 
bis(2,4,6-trimethylbenzoyl) phosphine oxide (BTMPO)]. Pre-coated PEEKs were 
bonded to PEEK blocks with a MMA-based adhesive resin. The shear bond strength 
was measured using a universal testing machine. Secondary electron images were 
captured to observe failure surfaces. The data were analyzed with one- and 
two-way ANOVA and Tukey's post hoc tests (p<0.05). The highest bond strength 
(20.7±5.1 MPa) was observed for pre-coating with MMA containing 0.4 wt% BTMPO, 
for 20 s of UV irradiation. Cohesive failure of the adhesive resin was observed. 
The use of this pre-coating led to improved bonding performance of PEEK.

DOI: 10.4012/dmj.2020-068
PMID: 33361659 [Indexed for MEDLINE]