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1.
Molecules ; 29(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38731478

RESUMEN

Microwave-assisted organic synthesis (MAOS) has emerged as a transformative technique in organic chemistry, significantly enhancing the speed, efficiency, and selectivity of chemical reactions. In our research, we have employed microwave irradiation to expedite the synthesis of quinazolinones, using water as an eco-friendly solvent and thereby adhering to the principles of green chemistry. Notably, the purification of the product was achieved without the need for column chromatography, thus streamlining the process. A key innovation in our approach is using aldehyde bisulfite adducts (Bertagnini's salts) as solid surrogates of aldehydes. Bertagnini's salts offer several advantages over free aldehydes, including enhanced stability, easier purification, and improved reactivity. Green metrics and Eco-Scale score calculations confirmed the sustainability of this approach, indicating a reduction in waste generation and enhanced sustainability outcomes. This methodology facilitates the synthesis of a diverse array of compounds, offering substantial contributions to the field, with potential for widespread applications in pharmaceutical research and beyond.

2.
RSC Adv ; 13(49): 34847-34851, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-38035248

RESUMEN

An N-alkylation procedure has been developed under very mild conditions using a known commercially available Ru-based catalyst. As a result, a wide range of aromatic primary amines has been selectively alkylated with several primary alcohols, yielding the corresponding secondary amines in high yields. The methodology also enables the methylation of anilines in refluxing methanol and the preparation of a set of heterocycles in a straightforward way.

3.
Vet Anaesth Analg ; 50(1): 9-20, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34838435

RESUMEN

OBJECTIVE: To explore the satisfaction and well-being experienced by anaesthesia residents during their training, and to investigate factors that may have influenced their experiences. STUDY DESIGN: Cross-sectional online anonymous voluntary survey. SAMPLE POPULATION: A total of 150 (of approximately 600 canvassed) former veterinary anaesthesia residents. METHODS: Participants were invited to complete an internet-based survey regarding the satisfaction and well-being experienced during their residency. Multiple choice, categorical, dichotomous, Likert-type rating scales and slider questions were used to investigate five domains (demographic, working conditions, educational environment, training satisfaction, well-being). Sampling adequacy, questionnaire reliability and participant responses were investigated by Kaiser-Meyer-Olkin (KMO) indices, Cronbach's α and standard statistical techniques, respectively (p < 0.05). RESULTS: The questionnaire demonstrated good sampling adequacy (median KMO index 0.74; range 0.51-0.89) and high item 'reliability' (α = 0.82-0.94). Of the 150 responders, (25% participation rate) 62% were satisfied, 14% were neutral and 24% were dissatisfied with their residency training; 60.6% would do the residency again, 39.3% would not or were unsure. Sex and age did not correlate with training satisfaction (p > 0.05). Salary/stipend was considered inadequate by 70% of responders; 66% received no on-call supplement. Greater supervisory input, a good working environment and extra income when on-call were positively correlated with training satisfaction (p < 0.01). The majority (94.6%) of trainees suffered from at least one medical condition during their residency, with fatigue, sleep disturbance or anxiety reported by > 62%. CONCLUSIONS: Although a quarter of responders were dissatisfied with their residency, several modifiable factors were identified, particularly with respect to supervisors' input, working environment and pay, which could inform improvements for future residency programmes. Most trainees experienced negative health impacts; however, this parallels the general situation in both the medical and veterinary professions, which requires greater attention from the supervisors, trainees and colleges.


Asunto(s)
Anestesia , Educación en Veterinaria , Internado y Residencia , Satisfacción Personal , Anestesia/veterinaria , Estudios Transversales , Educación en Veterinaria/estadística & datos numéricos , Encuestas y Cuestionarios , Humanos
4.
Molecules ; 27(22)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36432044

RESUMEN

The straightforward, continuous-flow synthesis of cyclopropyl carbaldehydes and ketones has been developed starting from 2-hydroxycyclobutanones and aryl thiols. This acid-catalyzed mediated procedure allows access to the multigram and easily scalable synthesis of cyclopropyl adducts under mild conditions, using reusable Amberlyst-35 as a catalyst. The resins, suitably ground and used for filling steel columns, have been characterized via TGA, ATR, SEM and BET analyses to describe the physical-chemical properties of the packed bed and the continuous-flow system in detail. To highlight the synthetic versatility of the arylthiocyclopropyl carbonyl compounds, a series of selective oxidation reactions have been performed to access sulfoxide and sulfone carbaldehyde cyclopropanes, oxiranes and carboxylic acid derivatives.


Asunto(s)
Ciclopropanos , Cetonas , Estructura Molecular , Ciclización , Catálisis , Ciclopropanos/química
5.
Beilstein J Org Chem ; 18: 1210-1216, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36158174

RESUMEN

Two easily accessible routes for preparing an array of formylated and acetylated amines under mechanochemical conditions are presented. The two methodologies exhibit complementary features as they enable the derivatization of aliphatic and aromatic amines.

6.
Beilstein J Org Chem ; 18: 732-737, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35821692

RESUMEN

Isocyanides are hardly produced, dramatically sensitive to purification processes, and complex to handle as synthetic tools. Notwithstanding, they represent one of the most refined and valuable compounds for accessing sophisticated and elegant synthetic routes. A unique interest has always been addressed to their production, though their synthetic pathways usually involve employing strong conditions and toxic reagents. The current paper intends to provide a conceptually innovative synthetic protocol for mechanochemical isocyanide preparation, simultaneously lowering the related reagents' toxicity and improving their purification in a straightforward procedure.

7.
ChemSusChem ; 15(17): e202200362, 2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-35867602

RESUMEN

Mechanochemical transformations have made chemists enter unknown territories, forcing a different chemistry perspective. While questioning or revisiting familiar concepts belonging to solution chemistry, mechanochemistry has broken new ground, especially in the panorama of organic synthesis. Not only does it foster new "thinking outside the box", but it also has opened new reaction paths, allowing to overcome the weaknesses of traditional chemistry exactly where the use of well-established solution-based methodologies rules out progress. In this Review, the reader is introduced to an intriguing research subject not yet fully explored and waiting for improved understanding. Indeed, the study is mainly focused on organic transformations that, although impossible in solution, become possible under mechanochemical processing conditions, simultaneously entailing innovation and expanding the chemical space.


Asunto(s)
Técnicas de Química Sintética
8.
Molecules ; 27(6)2022 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-35335350

RESUMEN

In just a few years, chemists have significantly changed their approach to the synthesis of organic molecules in the laboratory and industry. Researchers are encouraged to approach "greener" reagents, solvents, and methodologies, to go hand in hand with the world's environmental matter, such as water, soil, and air pollution. The employment of plant and animal derivates that are commonly regarded as "waste material" has paved the way for the development of new green strategies. In this review, the most important innovations in this field have been highlighted, paying due attention to those materials that have played a crucial role in organic reactions: wool, silk, and feather. Moreover, we decided to focus on the other most important supports and catalysts in green syntheses, such as proteins and their derivates. Different materials have shown prominent activity in the adsorption of metals and organic dyes, which has constituted a relevant scope in the last two decades. We intend to furnish a complete screening of the application given to these materials and contribute to their potential future utilization.


Asunto(s)
Tecnología Química Verde , Residuos , Catálisis , Solventes/química , Agua
9.
10.
Res Vet Sci ; 139: 43-50, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34246942

RESUMEN

The parasympathetic tone activity (PTA) index is based on heart rate variability and has been developed recently in animals to assess their relative parasympathetic tone. This study aimed to evaluate PTA index in anaesthetized horses with different health conditions and the performance of PTA variations (∆PTA) to predict changes in mean arterial pressure (MAP). Thirty-nine client-horses were anaesthetized for elective or colic surgery and divided into "Elective" and "Colic" groups. During anaesthesia, dobutamine was administered as treatment of hypotension (MAP <60 mmHg). In both groups, no significant variation of PTA and MAP were detected immediately before and after cutaneous incision. The PTA index increased 5 min before each hypotension, whereas it decreased 1 min after dobutamine administration. Horses of the Colic group had lower PTA values than those of the Elective group, whereas MAP did not differ between groups. To predict a 10% decrease in MAP, ΔPTA performance was associated with: AUC ROC [95% CI] =0.80 [0.73 to 0.85] (p < 0.0001), with a sensitivity of 62.5% and a specificity of 94.6% for a threshold value of 25%. The PTA index in anaesthetized horses appears to be influenced by the health condition. The shift toward lower PTA values in colic horses may reflect a sympathetic predominance. An increase in PTA of >25% in 1 min showed an acceptable performance to predict MAP decrease of >10% within 5 min. Even though these results require further evaluation, this index may thus help to predict potential autonomic dysfunctions in sick animals.


Asunto(s)
Anestesia , Presión Arterial , Caballos , Sistema Nervioso Parasimpático , Anestesia/veterinaria , Animales , Presión Sanguínea , Dobutamina , Frecuencia Cardíaca , Caballos/fisiología , Sistema Nervioso Parasimpático/efectos de los fármacos , Sistema Nervioso Parasimpático/fisiología
11.
Am J Vet Res ; 82(7): 574-581, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34166089

RESUMEN

OBJECTIVE: To compare the sublingual microcirculation between healthy horses anesthetized for elective procedures and horses with colic anesthetized for abdominal surgery and to determine the effect of mean arterial blood pressure (MAP) on the microcirculation. ANIMALS: 9 horses in the elective group and 8 horses in the colic group. PROCEDURES: Sublingual microcirculation was assessed with sidestream dark field video microscopy. Videos were captured at 3 time points during anesthesia. Recorded microvasculature parameters were De Backer score (DBS), total density of perfused vessels (PVD) and small vessels (PVD-S), total proportion of perfused vessels (PPV) and small vessels (PPV-S), vascular flow index (MFI), and heterogeneity index (HI). Blood pressure during hypotensive (MAP < 60 mm Hg) and normotensive (MAP ≥ 60 mm Hg) episodes was also recorded. RESULTS: During normotensive episodes, the elective group had significantly better PPV and PPV-S versus the colic group (median PPV, 76% vs 50%; median PPV-S, 73% vs 51%). In both groups, PPV decreased during anesthesia (elective group, -29%; colic group, -16%) but significantly improved in the elective group 15 minutes before the end of anesthesia (59%). During hypotensive episodes, PVD-S was better preserved in the colic group (11.1 vs 3.8 mm/mm2). No differences were identified for the microcirculatory parameters between normo- and hypotensive episodes in the colic group. CONCLUSIONS AND CLINICAL RELEVANCE: Sublingual microcirculation was better preserved in healthy horses anesthetized for elective procedures than in horses with colic anesthetized for abdominal surgery despite resuscitation maneuvers. Results indicated that the macrocirculation and microcirculation in critically ill horses may be independent.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Suelo de la Boca , Animales , Procedimientos Quirúrgicos del Sistema Digestivo/veterinaria , Hemodinámica , Caballos , Microcirculación , Microscopía por Video/veterinaria , Suelo de la Boca/cirugía
12.
Chem Commun (Camb) ; 56(75): 11066-11069, 2020 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-32812561

RESUMEN

A family of acyclic squaramide receptors (L1-L5) have been synthesised with the aim to bind anions in a competitive solvent mixture and to evaluate how the presence of additional H-bond donor groups on the squaramide scaffold could affect the affinity towards anions and the transmembrane transport ability.

13.
Chempluschem ; 85(7): 1389-1395, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32608173

RESUMEN

The anion binding ability of a family of bis-selenoureas L1-L3 obtained by the reaction of 1,3-bis(aminomethyl)-benzene and phenylisoselenocyanate, p-methoxyphenylisoselenocyanate and naphtylisoselenocyanate, for L1, L2, and L3, respectively, has been tested and compared to that of previously described bis-urea analogues. Results suggest that the introduction of selenium leads to an increase in the acidity of the urea NH hydrogen atoms, and therefore to a stronger affinity (more than three-fold higher) towards anion species, in particular dihydrogen phosphate, in DMSO-d6 . Theoretical calculations allowed for the optimization of the adducts receptors corroborating the experimental results.


Asunto(s)
Modelos Teóricos , Compuestos de Organoselenio/metabolismo , Espectroscopía de Protones por Resonancia Magnética/métodos , Urea/análogos & derivados , Aniones , Sitios de Unión , Teoría Funcional de la Densidad , Termodinámica , Urea/metabolismo
14.
Chemistry ; 26(67): 15589-15595, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32337746

RESUMEN

Cobalt-doped hybrid materials consisting of metal oxides and carbon derived from chitin were prepared, characterized and tested for industrially relevant nitrile hydrogenations. The optimal catalyst supported onto MgO showed, after pyrolysis at 700 °C, magnesium oxide nanocubes decorated with carbon-enveloped Co nanoparticles. This special structure allows for the selective hydrogenation of diverse and demanding nitriles to the corresponding primary amines under mild conditions (e.g. 70 °C, 20 bar H2 ). The advantage of this novel catalytic material is showcased for industrially important substrates, including adipodinitrile, picolinonitrile, and fatty acid nitriles. Notably, the developed system outperformed all other tested commercial catalysts, for example, Raney Nickel and even noble-metal-based systems in these transformations.

15.
Angew Chem Int Ed Engl ; 57(9): 2423-2426, 2018 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-29334423

RESUMEN

Mechanochemical activation of iron cyano complexes by ball milling results in the formation of HCN, which can be trapped and incorporated into α-aminonitriles. This prebiotic impact scenario can be extended by mechanochemically transforming the resulting α-aminonitriles into α-amino amides using a chemical route related to early Earth conditions.

16.
Res Vet Sci ; 115: 271-277, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28575801

RESUMEN

The Parasympathetic Tone Activity (PTA) is an index based on the analysis of heart rate variability that has been recently developed to assess the analgesia/nociception balance in anaesthetised animals. The present study aimed to evaluate its performance in dogs undergoing surgery. Thirty dogs admitted for elective surgeries, were anaesthetised with a standardised protocol. PTA, heart rate (HR), systolic blood pressure (SBP) and HDR (defined as an increase by >20% in HR and/or SBP within 5min) were assessed at the following predefined time-points: TStSt (steady-state, after induction of anaesthesia and before start of surgery), TClamp (clamping of surgical drapes on the skin), TCut (cutaneous incision), TPrePTA (retrospectively assessed 1min before a PTA decline of at least 20%) and TEndIso (isoflurane discontinuation). The dynamic variation of PTA over 1min (∆PTA) was calculated at each predefined time-points and its performance to predict HDR was assessed by building Receiver Operating Characteristics (ROC) curves. A significant decrease of PTA (p<0.002) was detected 1min after TClamp, TCut and TPrePTA followed by a significant increase in HR and/or SBP within 5min after the time points (p<0.01). The ΔPTA was associated with the following performance in predicting HDR: AUC ROC [95% CI]=0.80 [0.71 to 0.88] (p<0.05), with a sensitivity of 77% and a specificity of 72% for a threshold value of -18%. Although encouraging, the performance of the PTA index and its dynamic variation needs to be further evaluated, particularly in different clinical contexts.


Asunto(s)
Analgesia/veterinaria , Perros/fisiología , Frecuencia Cardíaca , Nocicepción , Sistema Nervioso Parasimpático/fisiología , Anestesia General/veterinaria , Animales , Presión Sanguínea , Perros/cirugía , Curva ROC , Sensibilidad y Especificidad
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