E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Special Issue "New Studies on the Synthesis of Biologically Active Products"

A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Organic Chemistry".

Deadline for manuscript submissions: 30 September 2019

Special Issue Editor

Guest Editor
Prof. Dr. Vincenzo Piccialli

Universita degli Studi di Napoli Federico II, Department of Chemical Sciences, Naples, Italy
Website | E-Mail
Interests: organic synthesis; new synthetic methods; medicinal chemistry; structure–activity relationship (SAR); biological activity; oxidation methods; catalytic processes; marine natural substances

Special Issue Information

Dear Colleagues,

The search for novel biologically-active substances is a major goal of medicinal chemistry, as highlighted by the emergency represented by the need for, as examples, new antibacterial or antiviral substances. Nature is very often the source of new lead compounds that constitute the starting point for the elaboration of new drugs. However, nature is sometimes miserly and substances possessing important biological activities are often obtained only in minute amounts from the natural source. In this context, synthetic organic chemists play a central role as witnessed by their incessant efforts to increase the biological effectiveness of known or new drugs through suitable structural modifications of the basic molecular architecture or to devise efficient routes to access such products in the required quantities. The construction of structurally complex molecules can be the bench test to verify the effectiveness of emerging synthetic methodologies or to discover new processes. Although this can imply a certain level of risk, synthetic plans, including new processes, intrinsically possess an added value and often contribute to the advancement of the science of organic synthesis. It is also worth highlighting that the work of synthetic chemists is increasingly supported by the close collaboration with biologists.

The purpose of this Special Issue is to gather original articles and reviews dealing with the synthesis of biologically active substances. According to the premise, synthetic studies accompanied by biological assays, or reporting new evidence on the use of known or emerging synthetic methods, would be very welcome.

Prof. Dr. Vincenzo Piccialli
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Molecules is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1800 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Organic synthesis
  • New synthetic methods
  • Medicinal chemistry
  • Structure–activity relationship (SAR)
  • Biological activity

Published Papers (4 papers)

View options order results:
result details:
Displaying articles 1-4
Export citation of selected articles as:

Research

Open AccessArticle
New γ-Halo-δ-lactones and δ-Hydroxy-γ-lactones with Strong Cytotoxic Activity
Molecules 2019, 24(10), 1875; https://doi.org/10.3390/molecules24101875
Received: 24 April 2019 / Revised: 7 May 2019 / Accepted: 9 May 2019 / Published: 15 May 2019
PDF Full-text (1642 KB) | HTML Full-text | XML Full-text
Abstract
This paper presents the synthesis of γ-halo-δ-lactones, δ-iodo-γ-lactones and δ-hydroxy-γ-lactones from readily available organic substrates such as trans-crotonaldehyde and aryl bromides. Crystal structure analysis was carried out for lactones that were obtained in [...] Read more.
This paper presents the synthesis of γ -halo- δ -lactones, δ -iodo- γ -lactones and δ -hydroxy- γ -lactones from readily available organic substrates such as trans-crotonaldehyde and aryl bromides. Crystal structure analysis was carried out for lactones that were obtained in crystalline form. All halo- δ -lactones and δ -hydroxy- γ -lactones were highly cytotoxic against gastric cancer AGS cells with I C 50 values in the range of 0.0006–0.0044 mM. Some lactones showed high bactericidal activity against E. coli ATCC 8739 and S. aureus ATCC 65389, which reduced the number of CFU/mL by 70–83% and 87% respectively. Full article
(This article belongs to the Special Issue New Studies on the Synthesis of Biologically Active Products)
Figures

Graphical abstract

Open AccessArticle
A Simple and Efficient Method for the Partial Synthesis of Pure (3R,3’S)-Astaxanthin from (3R,3’R,6’R)-Lutein and Lutein Esters via (3R,3’S)-Zeaxanthin and Theoretical Study of Their Formation Mechanisms
Molecules 2019, 24(7), 1386; https://doi.org/10.3390/molecules24071386
Received: 26 March 2019 / Revised: 6 April 2019 / Accepted: 7 April 2019 / Published: 9 April 2019
PDF Full-text (3822 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Carotenoids are natural compounds that have important roles in promoting and maintaining human health. Synthetic astaxanthin is a highly requested product by the aquaculture industry, but natural astaxanthin is not. Various strategies have been developed to synthesize this carotenoid. Nonetheless, these approaches have [...] Read more.
Carotenoids are natural compounds that have important roles in promoting and maintaining human health. Synthetic astaxanthin is a highly requested product by the aquaculture industry, but natural astaxanthin is not. Various strategies have been developed to synthesize this carotenoid. Nonetheless, these approaches have not only provided limited global yields, but its main commercial source also carries several health risks for humans. In this contribution, the one-pot base-catalyzed reaction of (3R,3’R,6’R)-lutein (1) esters has resulted in a successful isomerization process to easily obtain up to 95% meso-zeaxanthin (2), which in turn is oxidized to (3R,3’S)-astaxanthin (3) with a global yield of 68%. The same oxidation performed with UV irradiation (365 nm) for 5 min provided the highest global yield (76%). These chemical transformations have also been achieved with a significant reduction of the health risks associated with its potential human consumption. Furthermore, this is the first time only one of the configurational isomers has been obtained semisynthetically. The poorly understood formation mechanisms of these two compounds were also investigated using Density-Functional Theory (DFT) calculations. These theoretical studies revealed that the isomerization involves a base-catalyzed deprotonation at C-6’, followed by C-4’ protonation, while the oxidation occurs via free radical mechanisms. Full article
(This article belongs to the Special Issue New Studies on the Synthesis of Biologically Active Products)
Figures

Graphical abstract

Open AccessArticle
An Improved Method for the Quaternization of Nicotinamide and Antifungal Activities of Its Derivatives
Molecules 2019, 24(6), 1001; https://doi.org/10.3390/molecules24061001
Received: 27 February 2019 / Revised: 7 March 2019 / Accepted: 9 March 2019 / Published: 13 March 2019
PDF Full-text (1128 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The quaternization reactions of nicotinamide, with different electrophiles: methyl iodide and substituted 2-bromoacetophenones (4-Cl, 4-Br, 4-H, 4-CH3, 4-F, 4-OCH3, 4-Ph, 2-OCH3, 4-NO2) are reported. The preparations were carried out by conventional synthesis and under microwave [...] Read more.
The quaternization reactions of nicotinamide, with different electrophiles: methyl iodide and substituted 2-bromoacetophenones (4-Cl, 4-Br, 4-H, 4-CH3, 4-F, 4-OCH3, 4-Ph, 2-OCH3, 4-NO2) are reported. The preparations were carried out by conventional synthesis and under microwave irradiation in absolute ethanol and acetone. The synthesis performed by microwave dielectric heating significantly improved yield, up to 8 times, and shortened down the reaction time from ca. one day in conventional, to 10–20 min. The structures of the synthesized compounds were confirmed by IR, 1H- and 13C-NMR spectroscopy, mass spectrometry and elemental analysis. The compounds have been screened for antifungal activities against Fusarium oxysporum, Fusarium culmorum, Macrophomina phaseolina and Sclerotinia sclerotiorum at concentrations of 10 µg/mL and 100 µg/mL. Six compounds showed the strong inhibition of mycelium growth at a concentration of 10 µg/mL. All tested compounds revealed the great inhibitory activities against S. sclerotiorum at a concentration of 100 µg/mL. Full article
(This article belongs to the Special Issue New Studies on the Synthesis of Biologically Active Products)
Figures

Graphical abstract

Open AccessCommunication
Convenient Synthesis of Functionalized Cyclopropa[c]coumarin-1a-carboxylates
Received: 1 December 2018 / Revised: 15 December 2018 / Accepted: 22 December 2018 / Published: 24 December 2018
PDF Full-text (3115 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A simple method has been developed for the synthesis of cyclopropa[c]coumarins, which belong to the donor-acceptor cyclopropane family and, therefore, are promising substrates for the preparation of chromene-based fine chemicals. The method, based on the acetic acid-induced intramolecular transesterification of 2-arylcyclopropane-1,1-dicarboxylates, [...] Read more.
A simple method has been developed for the synthesis of cyclopropa[c]coumarins, which belong to the donor-acceptor cyclopropane family and, therefore, are promising substrates for the preparation of chromene-based fine chemicals. The method, based on the acetic acid-induced intramolecular transesterification of 2-arylcyclopropane-1,1-dicarboxylates, was found to be efficient for substrates containing hydroxy group directly attached to the aromatic ring. Full article
(This article belongs to the Special Issue New Studies on the Synthesis of Biologically Active Products)
Figures

Graphical abstract

Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

Title: Synthesis and DFT Study of New Benzimidazole Mannich Bases as Antimicrobial Agents
Author: Maria Marinescu
Abstract: Novel benzimidazole Mannich bases were synthesized from 2-hydroxyethyl- benzimidazole, amines and formaldehyde by a one-pot synthesis. The structures of the new compounds are confirmed by 1H, 13C NMR, FTIR, MS spectra and elemental analysis. All benzimidazole compounds were screened by qualitative and quantitative methods for their in vitro antibacterial activity against 4 bacterial strains. The best minimum inhibitory concentration (MIC) is observed for (S)-1-(1-((4-methylpiperazin-1-yl)methyl)-1H-benzo[d] imidazol-2-yl)ethanol on all tested strains. DFT studies were accomplished in order to optimize all Mannich bases using GAMESS 2012 software and HOMO-LUMO analysis allowed the calculation of electronic and structural parameters. Antimicrobial activity of the Manncih benzimidazoles is correlated with theirs electronic and geometric parameters, and also with Mullikan atomic charges on the atoms.
Molecules EISSN 1420-3049 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top