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1.
Steroids ; 199: 109286, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37517593

ABSTRACT

Four hybrid steroid dimers were obtained by BF3·Et2O-catalyzed aldol condensation of acetylated steroid sapogenins with 2-formyl-estradiol diacetate. The structures of the obtained dimers were unambiguously established by NMR. The hybrid dimers 9a (IC50 18.37 µM) and 9c (IC50 9.4 µM) with the 5α configuration at the A/B rings junction showed the higher cytotoxicity against HeLa, with selectivity index of 4.36 and 11.8 respectively. The presence of a carbonyl function at position C-12 produced the highest cytotoxic effect, which is in line with our previous reports.

2.
Steroids ; 188: 109110, 2022 12.
Article in English | MEDLINE | ID: mdl-36100111

ABSTRACT

23E-diacetoxybenzylidenespirostanes underwent rearrangement when treated with HCl in CH2Cl2/CH3OH. The course of the rearrangement depends on the substitution pattern in the phenyl ring. While compounds bearing an acetoxy group at the ortho position produced spirochromenes, the partners with no substituent at the ortho position led to spiroindenes. All the rearranged compounds exhibited moderate antioxidant activity.


Subject(s)
Acetals , Antioxidants , Catalysis
3.
Sensors (Basel) ; 22(10)2022 May 19.
Article in English | MEDLINE | ID: mdl-35632248

ABSTRACT

Facial motion analysis is a research field with many practical applications, and has been strongly developed in the last years. However, most effort has been focused on the recognition of basic facial expressions of emotion and neglects the analysis of facial motions related to non-verbal communication signals. This paper focuses on the classification of facial expressions that are of the utmost importance in sign languages (Grammatical Facial Expressions) but also present in expressive spoken language. We have collected a dataset of Spanish Sign Language sentences and extracted the intervals for three types of Grammatical Facial Expressions: negation, closed queries and open queries. A study of several deep learning models using different input features on the collected dataset (LSE_GFE) and an external dataset (BUHMAP) shows that GFEs can be learned reliably with Graph Convolutional Networks simply fed with face landmarks.


Subject(s)
Face , Facial Expression , Emotions , Humans , Recognition, Psychology , Sign Language
4.
Steroids ; 176: 108918, 2021 12.
Article in English | MEDLINE | ID: mdl-34562490

ABSTRACT

NaBH3CN reduction of symmetric dimers in which two steroid units are linked by a 1,4-dimethylidenebenzene moiety followed two different courses: (a) hydrogenation of the benzylic double bond and (b) reductive F ring opening of the side chain. While courses a and b led to symmetrical dimers, the combination of both pathways produced an unsymmetrical dimer that bears different side chains in each half. The exhaustive NMR characterization of all obtained compounds is presented.


Subject(s)
Steroids/chemistry , Dimerization , Molecular Conformation , Oxidation-Reduction , Stereoisomerism
5.
Angew Chem Int Ed Engl ; 60(34): 18489-18493, 2021 Aug 16.
Article in English | MEDLINE | ID: mdl-34159706

ABSTRACT

A novel stable donor/acceptor-supported MnI -metallasilanone 3 was synthesized. The intramolecular silanone-MnI interaction induces a highly strained three-membered cyclic structure, leading to an exceptionally high reactivity of 3 as a donor/acceptor complex of silanone. Indeed, metallasilanone 3 readily reacts with various small molecules such as H2 or ethylene gas in mild conditions.

6.
Steroids ; 151: 108462, 2019 11.
Article in English | MEDLINE | ID: mdl-31344407

ABSTRACT

A study of the reactivity of 25R and 25S 23E-benzylidene spirostanes that includes epoxidation, catalytic hydrogenation as well as Lewis or Brønsted acid-catalyzed rearrangements is described. Exhaustive NMR characterization of the obtained compounds is presented. Additionally the structures of some of the obtained compounds were confirmed by single crystal X-Ray Diffraction studies.


Subject(s)
Benzylidene Compounds/chemistry , Spirostans/chemistry , Catalysis , Hydrogenation , Models, Molecular , Molecular Conformation
7.
Steroids ; 140: 58-61, 2018 12.
Article in English | MEDLINE | ID: mdl-30149074

ABSTRACT

BF3·Et2O-catalyzed double aldol condensation between acetylated steroid sapogenins and terephtalaldehyde led to acetylated dimeric spirostanols linked through a 1,4-dimethylidenebenzene moiety in moderate to good yields. The E configurations of the introduced double bonds were corroborated by NOE experiments. Saponification of the dimeric steroids led to the corresponding dimeric spirostanols.


Subject(s)
Aldehydes/chemistry , Benzene/chemistry , Boranes/chemistry , Dimerization , Ether/chemistry , Phthalic Acids/chemistry , Sapogenins/chemistry , Spirostans/chemical synthesis , Catalysis , Chemistry Techniques, Synthetic , Spirostans/chemistry , Stereoisomerism
8.
Steroids ; 128: 46-49, 2017 12.
Article in English | MEDLINE | ID: mdl-29066328

ABSTRACT

BF3·Et2O-catalyzed aldol condensation of steroid sapogenins with 2-formyl-estradiol diacetate afforded two novel classes of steroid dimers in which an estrogenic core is attached to the spirostanic side chain of an steroid sapogenin through an exocyclic double bond in position C-23, or through a spiro centre in C-22.


Subject(s)
Aldehydes/chemistry , Estradiol/chemical synthesis , Sapogenins/chemistry , Steroids/chemistry , Aldehydes/chemical synthesis , Benzaldehydes/chemical synthesis , Benzaldehydes/chemistry , Catalysis , Estradiol/analogs & derivatives , Estradiol/chemistry , Magnetic Resonance Spectroscopy , Sapogenins/chemical synthesis , Stereoisomerism , Steroids/chemical synthesis
9.
Steroids ; 128: 85-88, 2017 12.
Article in English | MEDLINE | ID: mdl-28887172

ABSTRACT

Benzylidenespirostanols were prepared by two-step synthesis including BF3·Et2O-catalyzed aldol condensation of several acetylated steroid sapogenins with benzaldehyde followed by saponification. The obtained compounds showed moderate cytotoxicity against three cancer cell lines (T-lymphoblastic leukemia cell line CEM, breast carcinoma cell line MCF7 and cervical carcinoma cell line HeLa) and normal human fibroblasts (BJ). The most active of the five tested substances was 3c (lowest IC50 for MCF7 cells 19.9±0.1µM) without any selectivity towards human cancer and normal cells, respectively.


Subject(s)
Antineoplastic Agents, Phytogenic/chemical synthesis , Sapogenins/chemical synthesis , Spirostans/chemical synthesis , Steroids/chemical synthesis , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Screening Assays, Antitumor , Humans , MCF-7 Cells , Sapogenins/chemistry , Sapogenins/pharmacology , Spirostans/chemistry , Spirostans/pharmacology , Steroids/chemistry , Steroids/pharmacology
10.
PLoS One ; 11(6): e0157932, 2016.
Article in English | MEDLINE | ID: mdl-27362479

ABSTRACT

BACKGROUND: Several studies suggest that there is a pathogenic link between chronic obstructive pulmonary disease (COPD) and cardiovascular diseases. On the other hand, increased sympathetic tone has been described in several respiratory diseases. Our objective was to determine whether hypertension mediated by sympathetic overactivity is a mechanism that explains the association between COPD and cardiovascular diseases. METHODS: Prospective nested case-control observational study; 67 COPD patients were matched 1:1 by sex and age to controls with smoking history. 24 hour-blood pressure monitoring, urinary catecholamines and their metabolites measurement, echocardiography, carotid ultrasound examination, nocturnal oximetry and retinography were performed. FINDINGS: classic cardiovascular risk factors and comorbidities were similarly distributed between cases and controls. No significant differences for blood pressure variables (difference for mean systolic blood pressure: -0·13 mmHg; 95% CI: -4·48,4·20; p = 0·94; similar results for all blood presssure variables) or catecholamines values were found between both groups. There was a tendency for lower left ventricle ejection fraction in the COPD cases, that approached statistical significance (64·8 ± 7·4 vs 67·1 ± 6·2, p = 0·05). There were no differences in the retinal arteriovenous ratio, the carotid intima-media thickness, or the number of carotid plaques, between cases and controls. Fibrinogen values were higher in the COPD group (378·4 ± 69·6 vs 352·2 ± 45·6 mg/dL, p = 0·01) and mean nocturnal oxygen saturation values were lower for COPD patients (89·0 ± 4·07 vs 92·3 ± 2·2%, p < 0·0001). INTERPRETATION: Hypertension induced by sympathetic overactivity does not seem to be a mechanism that could explain the association between COPD and cardiovascular disease.


Subject(s)
Blood Pressure/physiology , Cardiovascular Diseases/epidemiology , Catecholamines/urine , Hypertension/complications , Pulmonary Disease, Chronic Obstructive/physiopathology , Aged , Blood Pressure Determination , Case-Control Studies , Female , Humans , Male , Middle Aged , Prospective Studies , Risk Factors
11.
Steroids ; 98: 132-7, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25824324

ABSTRACT

Tandem aldol condensation between steroid sapogenins and hydroxylated benzaldehydes afforded steroidal spirochromenes. Compounds that bear a phenolic hydroxyl group at position C-6', obtained by a reaction with 2,5-dihydroxybenzaldehyde, showed approximately 80% of maximal radical scavenging activity in the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) assay at 288 nM. In contrast, the starting steroid sapogenins and the spirochromenes without a phenolic group in the side chain proved to be inactive.


Subject(s)
Free Radical Scavengers/chemistry , Free Radical Scavengers/chemical synthesis , Sapogenins/chemistry
12.
An. salud ment ; 12(1/2): 195-203, 1996.
Article in Spanish | LILACS, LIPECS | ID: lil-666510

ABSTRACT

En la percepción del modelo ecológico se presenta un caso de gemelos monocigotos dependientes a múltiples drogas. Los gemelos desarrollaron la adicción a diferentes edades y con distintos grupos amicales. Ambos presentaron como dependencia principal adicción a la Pasta Básica de Cocaína y, secundariamente, al alcohol y a benzodiacepinas. Se discuten los mecanismo individuales, familiares y ambientes en el desarrollo de la enfermedad adictiva enfatizando que la dependencia de pasta básica de cocaína en gemelos monocigotos aún no ha sido descrita en la literatura médica nacional ni internacional.


In an ecological perspective a case of monozygotic twins with multiple drug addiction is presented. The addiction was established at different ages in both twins and sharing in distinct groups of friends. Both of them presented Basic Cocaine paste as the main addiction and to alcohol and benzodiazepines as a secondary one. The individual, familiar and environment mechanisms producing the addictive disorder are discussed, pointing out that dependence to Basic Cocaine Paste in monozygotic twins have not been describes in the national and international medical literatures as yet.


Subject(s)
Humans , Male , Adult , Alcoholism , Benzodiazepines , Twins, Monozygotic , Cocaine-Related Disorders , Substance-Related Disorders , Epidemiology, Descriptive , Observational Studies as Topic
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