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1.
Chempluschem ; : e202400442, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105675

RESUMEN

Brazil has one of the greatest biodiversities on the planet, where various crops play a strategic role in the country's economy. Among the highly appreciated biomasses is babassu, whose oil extraction generates residual babassu mesocarp (BM), which still needs new strategies for valorization. This work aimed to use BM as a support for the immobilization of Thermomyces lanuginosus lipase (TLL) in an 8.83 mL packed-bed reactor, followed by its application as a biocatalyst for the synthesis of hexyl laurate in an integrated process. Initially, the percolation of a solution containing 5 mg of TLL at 25 °C and flows ranging from 1.767 to 0.074 mL min-1 was investigated, where at the lowest flow rate tested (residence time of 2 h), it was possible to obtain an immobilized derivative with hydrolytic activity of 504.7 U g-1 and 31.7 % of recovered activity. Subsequent studies of treatment with n-hexane, as well as the effect of temperature on the immobilization process, were able to improve the activities of the final biocatalyst BM-TLLF, achieving a final hydrolysis activity of 7023 U g-1 and esterification activity of 430 U ⋅ g-1 against 142 U g-1 and 113.5 U g-1 respectively presented by the commercial TLIM biocatalyst. Desorption studies showed that the TL IM has 18 mg of protein per gram of support, compared to 4.92 mg presented by BM-TLL. Both biocatalysts were applied to synthesize hexyl laurate, achieving 98 % conversion at 40 °C within 2 h. Notably, BM-TLLF displayed exceptional recyclability, maintaining catalytic efficiency over 12 cycles. This reflects a productivity of 180 mg of product ⋅ h-1 U-1 of the enzyme, surpassing 46 mg h-1 U-1 obtained for TLIM. These results demonstrate the efficacy of continuous flow technology in creating a competitive and integrated process offering an exciting alternative for the valorization of residual lignocellulosic biomass.

2.
Chemistry ; 27(18): 5577-5600, 2021 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-32780909

RESUMEN

The current state of evidence and recommendations for cannabidiol (CBD) and its health effects change the legal landscape and aim to destigmatize its phytotherapeutic research. Recently, some countries have included CBD as an antiepileptic product for compassionate use in children with refractory epilepsy. The growing demand for CBD has led to the need for high-purity cannabinoids on the emerging market. The discovery and development of approaches toward CBD synthesis have arisen from the successful extraction of Cannabis plants for cannabinoid fermentation in brewer's yeast. To understand different contributions to the design and enhancement of the synthesis of CBD and its key intermediates, a detailed analysis of the history behind cannabinoid compounds and their optimization is provided herein.


Asunto(s)
Cannabidiol , Cannabinoides , Cannabis , Preparaciones Farmacéuticas , Anticonvulsivantes , Niño , Humanos
3.
Org Biomol Chem ; 17(6): 1552-1557, 2019 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-30693360

RESUMEN

Continuous-flow production of chiral intermediates plays an important role in the development of building blocks for Active Pharmaceutical Ingredients (APIs), being α-amino acids and their derivatives widely applied as building blocks. In this work we developed two different strategies for the synthesis of intermediates used on the synthesis of levetiracetam/brivaracetam and ethambutol. The results obtained show that methionine methyl ester can be continuously converted to the desired ethambutol intermediate by RANEY® Nickel dessulfurization/reduction strategy whereas levetiracetam/brivaracetam intermediates could be synthesized by both RANEY® Nickel (without H2) and Pd/C-H2 approach or by photochemical desulfurization.


Asunto(s)
Anticonvulsivantes/síntesis química , Anticonvulsivantes/farmacología , Antituberculosos/síntesis química , Antituberculosos/farmacología , Anticonvulsivantes/química , Antituberculosos/química , Técnicas de Química Sintética , Etambutol/síntesis química , Etambutol/química , Etambutol/farmacología , Levetiracetam/síntesis química , Levetiracetam/química , Levetiracetam/farmacología , Pirrolidinonas/síntesis química , Pirrolidinonas/química , Pirrolidinonas/farmacología , Estereoisomerismo , Azufre/química
4.
An Acad Bras Cienc ; 90(1 Suppl 2): 1273-1278, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29768577

RESUMEN

New acylhydrazone-based palladacycles are prepared and evaluated as pre-catalysts in Mirozoki-Heck and oxyarylation reactions.

5.
Bioorg Med Chem ; 26(7): 1333-1337, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28802669

RESUMEN

Crizotinib is an anti-cancer agent approved for treatment of non-small cell lung carcinoma. Retrosynthetic analysis revels 1-(2,6-dichloro-3-fluorophenyl)ethanol as an important intermediate, which can be made available by different biocatalytic approaches. Herein we report our results on the kinetic and dynamic resolution towards the desired chiral intermediate for Crizotinib synthesis. The results obtained show that very good conversions and high selectivity could be obtained for the kinetic resolution (45% conv. and E>200) while dynamic kinetic resolution under continuous-flow conditions afforded the desired product in 57% conversion and 98% e.e.


Asunto(s)
Simulación de Dinámica Molecular , Pirazoles/química , Piridinas/química , Crizotinib , Cinética , Estructura Molecular
6.
Chem Biol Drug Des ; 81(2): 185-97, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22985449

RESUMEN

Recently, many efforts have been made to develop N-methyl-D-aspartic acid receptor antagonists for treating different pathological conditions such as thrombo-embolic stroke, traumatic head injury, Huntington's, Parkinson's, and Alzheimer's diseases). However, as side-effects limit the use of most antagonists, new drugs are still required. In this work, we performed a (quantitative) structure-activity relationship analysis of 17 phenyl-amidine derivatives (1a-1q), reported as N-methyl-D-aspartic acid receptor antagonists, and used this data to rationally design the triazolyl-amidines. The best (quantitative) structure-activity relationship model constructed by multiple linear regression analysis presented high data fitting (R = 0.914) was able to explain 83.6% of the biological data variance (R(2) = 0.836), presented a satisfactory internal predictive ability (Q(2) = 0.609) and contained the descriptors (E(HOMO), Ovality and cLogP). Our assays confirmed that glutamate promotes an extensive cell death in avian neurons (77%) and 2a and 2b protected the neurons from the glutamate effect (from 77% to 27% and 45%, respectively). The results of neurotoxicity and cytotoxicity on Vero cells suggested the favorable profile of 2a and 2b. Also, the molecular modeling used to predict the activity, the interaction with the receptor and the pharmacokinetic and toxicity of the triazolyl-amidines pointed them as a promising class for further exploration as N-methyl-D-aspartic acid receptor antagonists.


Asunto(s)
Amidinas/química , Fármacos Neuroprotectores/química , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Triazoles/química , Amidinas/farmacología , Animales , Muerte Celular , Chlorocebus aethiops , Ácido Glutámico/toxicidad , Simulación del Acoplamiento Molecular , Fármacos Neuroprotectores/farmacología , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/metabolismo , Neuronas Retinianas/citología , Neuronas Retinianas/efectos de los fármacos , Relación Estructura-Actividad , Triazoles/farmacología , Células Vero
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