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1.
RSC Adv ; 12(14): 8588-8591, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35424822

RESUMEN

Planar chiral [2.2]paracyclophanes are resolved through the direct C-H arylation of enantiopure oxazolines, providing a convenient route to ligands and chiral materials. Preliminary results show that hydrolysis followed by decarboxylative phosphorylation leads to enantiopure [2.2]paracyclophane derivatives that are otherwise challenging to prepare.

2.
Int J Gynecol Pathol ; 41(5): 476-483, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34570018

RESUMEN

Vulval extramammary Paget disease (vEMPD) is an uncommon epithelial malignancy that may arise within the vulva (primary vEMPD) or represent vulval skin involvement by a noncutaneous carcinoma (secondary vEMPD). Primary vEMPD is most often an in situ carcinoma arising within the epidermis but may be associated with dermal invasion (invasive vEMPD) or represent intraepidermal spread of an adenocarcinoma originating in vulval skin adnexa or anogenital mammary-like glands. The latter, termed mammary gland-like adenocarcinoma (MGLA), exhibits morphologic, immunohistochemical, and molecular features of various breast carcinomas but, as far as we are aware, the metaplastic variant of MGLA has not been reported on the vulva. We report 2 cases of metaplastic MGLA of the vulva with associated Paget disease and postulate that some cases of vulval MGLA may arise from Paget disease rather than originating in mammary-like glands. We also report a unique case of secondary vEMPD resulting from spread of urothelial carcinoma in situ that subsequently progressed to invasive urothelial carcinoma within the vulva.


Asunto(s)
Adenocarcinoma , Neoplasias de la Mama , Carcinoma de Células Transicionales , Enfermedad de Paget Extramamaria , Neoplasias de la Vejiga Urinaria , Neoplasias de la Vulva , Adenocarcinoma/patología , Femenino , Humanos , Enfermedad de Paget Extramamaria/diagnóstico , Enfermedad de Paget Extramamaria/patología , Neoplasias de la Vulva/diagnóstico , Neoplasias de la Vulva/patología
3.
mSphere ; 6(5): e0062721, 2021 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-34494879

RESUMEN

Effective therapeutic options are urgently needed to tackle antibiotic resistance. Furazolidone (FZ), vancomycin (VAN), and sodium deoxycholate (DOC) show promise as their combination can synergistically inhibit the growth of, and kill, multidrug-resistant Gram-negative bacteria that are classified as critical priority by the World Health Organization. Here, we investigated the mechanisms of action and synergy of this drug combination using a transcriptomics approach in the model bacterium Escherichia coli. We show that FZ and DOC elicit highly similar gene perturbations indicative of iron starvation, decreased respiration and metabolism, and translational stress. In contrast, VAN induced envelope stress responses, in agreement with its known role in peptidoglycan synthesis inhibition. FZ induces the SOS response consistent with its DNA-damaging effects, but we demonstrate that using FZ in combination with the other two compounds enables lower dosages and largely mitigates its mutagenic effects. Based on the gene expression changes identified, we propose a synergy mechanism where the combined effects of FZ, VAN, and DOC amplify damage to Gram-negative bacteria while simultaneously suppressing antibiotic resistance mechanisms. IMPORTANCE Synergistic antibiotic combinations are a promising alternative strategy for developing effective therapies for multidrug-resistant bacterial infections. The synergistic combination of the existing antibiotics nitrofurans and vancomycin with sodium deoxycholate shows promise in inhibiting and killing multidrug-resistant Gram-negative bacteria. We examined the mechanism of action and synergy of these three antibacterials and proposed a mechanistic basis for their synergy. Our results highlight much-needed mechanistic information necessary to advance this combination as a potential therapy.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Ácido Desoxicólico/farmacología , Combinación de Medicamentos , Sinergismo Farmacológico , Furazolidona/farmacología , Vancomicina/farmacología
4.
Beilstein J Org Chem ; 17: 1518-1526, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34285723

RESUMEN

Substituted [2.2]metaparacyclophanes are amongst the least studied of the simple cyclophanes. This is undoubtedly the result of the lengthy syntheses of these compounds. We report the simple synthesis of a rare example of a non-symmetric [2.2]metaparacyclophane. Treatment of [2.2]paracyclophane under standard nitration conditions gives a mixture of 4-nitro[2.2]paracyclophane, 4-hydroxy-5-nitro[2.2]metaparacyclophane and a cyclohexadienone cyclophane.

5.
Int J Gynecol Cancer ; 31(2): 286-291, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32907814

RESUMEN

BACKGROUND: Risk-reducing salpingo-oophorectomy is the 'gold standard' for preventing tubo-ovarian cancer in women at increased risk. However, when performed in pre-menopausal women, it results in premature menopause and associated detrimental health consequences. This, together with acceptance of the central role of the fallopian tube in etiopathogenesis of high-grade serous carcinoma, by far the most common type of tubo-ovarian cancer, has led to risk-reducing early salpingectomy with delayed oophorectomy being proposed as a two-step surgical alternative for pre-menopausal women declining/delaying oophorectomy. PRIMARY OBJECTIVE: To evaluate the impact on sexual function of risk-reducing early salpingectomy, within a two-step, risk-reducing, early salpingectomy with delayed oophorectomy tubo-ovarian cancer prevention strategy in pre-menopausal women at increased risk of tubo-ovarian cancer. STUDY HYPOTHESIS: Risk-reducing early salpingectomy is non-inferior for sexual and endocrine function compared with controls; risk-reducing early salpingectomy is superior for sexual/endocrine function, non-inferior for quality-of-life, and equivalent in satisfaction to the standard risk-reducing salpingo-oophorectomy. TRIAL DESIGN: Multi-center, observational cohort trial with three arms: risk-reducing early salpingectomy with delayed oophorectomy; risk-reducing salpingo-oophorectomy; controls (no surgery). Consenting individuals undergo an ultrasound, serum CA125, and follicle-stimulating hormone measurements and provide information on medical history, family history, quality-of-life, sexual function, cancer worry, psychological well-being, and satisfaction/regret. Follow-up by questionnaire takes place annually for 3 years. Women receiving risk-reducing early salpingectomy can undergo delayed oophorectomy at a later date of their choosing, or definitely by the menopause. MAJOR INCLUSION/EXCLUSION CRITERIA: Inclusion criteria: pre-menopausal; aged >30 years; at increased risk of tubo-ovarian cancer (mutation carriers or on the basis of a strong family history); completed their family (for surgical arms). EXCLUSION CRITERIA: post-menopausal; previous bilateral salpingectomy or bilateral oophorectomy; pregnancy; previous tubal/ovarian/peritoneal malignancy; <12 months after cancer treatment; clinical suspicion of tubal/ovarian cancer at baseline. PRIMARY ENDPOINT: Sexual function measured by validated questionnaires. SAMPLE SIZE: 1000 (333 per arm). ESTIMATED DATES FOR COMPLETING ACCRUAL AND PRESENTING RESULTS: It is estimated recruitment will be completed by 2023 and results published by 2027. TRIAL REGISTRATION NUMBER: ISRCTN registry: 25 173 360 (https://doi.org/10.1186/ISRCTN25173360).


Asunto(s)
Neoplasias Quísticas, Mucinosas y Serosas/prevención & control , Neoplasias Ováricas/prevención & control , Ovariectomía/métodos , Proteína BRCA1 , Proteína BRCA2 , Femenino , Humanos , Estudios Multicéntricos como Asunto , Neoplasias Quísticas, Mucinosas y Serosas/genética , Neoplasias Ováricas/genética , Ovariectomía/efectos adversos , Premenopausia , Estudios Prospectivos
6.
J Org Chem ; 85(17): 11297-11308, 2020 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-32786648

RESUMEN

Quinolino[7,8-h]quinoline is a superbasic compound, with a pKaH in acetonitrile greater than that of 1,8-bis(dimethylaminonaphthalene) (DMAN), although its synthesis and the synthesis of its derivatives can be problematic. The use of halogen derivatives 4,9-dichloroquinolino[7,8-h]quinoline (16) and 4,9-dibromoquinolino[7,8-h]quinoline (17) as precursors has granted the formation of a range of substituted quinolinoquinolines. The basicity and other properties of quinolinoquinolines can be modified by the inclusion of suitable functionalities. The experimentally obtained pKaH values of quinolino[7,8-h]quinoline derivatives show that N4,N4,N9,N9-tetraethylquinolino[7,8-h]quinoline-4,9-diamine (26) is more superbasic than quinolino[7,8-h]quinoline. Computationally derived pKaH values of quinolinoquinolines functionalized with dimethylamino (NMe2), 1,1,3,3-tetramethylguanidino (N═C(NMe2)2) or N,N,N',N',N″,N″-hexamethylphosphorimidic triamido (N═P(NMe2)3) groups are significantly greater than those of quinolino[7,8-h]quinoline. Overall, electron-donating functionalities are observed to increase the basicity of the quinolinoquinoline moiety, while the substitution of electron-withdrawing groups lowers the basicity.

7.
Int J Gynecol Pathol ; 39(1): 97-102, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31815894

RESUMEN

Angiosarcomas of the female genital tract are rare and primary angiosarcoma of the cervix is extremely rare with only one prior case report. We report a case of a primary cervical angiosarcoma in a 43-yr-old woman who presented with heavy vaginal bleeding. Cervical biopsy and subsequent radical hysterectomy showed a malignant vascular tumor which was composed of spindled and epithelioid cells and formed abortive vascular channels. Immunohistochemically, the tumor cells were diffusely positive for CD31, CD34, ERG, and cyclin D1 and focally positive for D2-40. A reverse transcription polymerase chain reaction test for YWHAE-NUTM2 genetic fusion was negative excluding a YWHAE-translocated high-grade endometrial stromal sarcoma. The tumor formed a 5 cm mass within the cervix with microscopic involvement of the endometrium, superficial myometrium, and vagina. Metastatic microscopic tumor deposits were present in both ovaries, left fallopian tube, one paracervical lymph node, and one pelvic lymph node. In reporting this unusual case we discuss the differential diagnosis.


Asunto(s)
Hemangiosarcoma/diagnóstico , Hemangiosarcoma/patología , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/patología , Adulto , Diagnóstico Diferencial , Neoplasias Endometriales/diagnóstico , Neoplasias Endometriales/patología , Femenino , Humanos , Inmunohistoquímica , Metástasis de la Neoplasia , Sarcoma Estromático Endometrial/diagnóstico , Sarcoma Estromático Endometrial/patología
9.
Org Biomol Chem ; 15(42): 8975-8984, 2017 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-29043364

RESUMEN

The synthesis of three planar chiral pseudo-gem disubstituted [2.2]paracyclophane-derived P,N-pre-ligands is reported along with preliminary results of their activity in the amination of aryl bromides and chlorides. The pseudo-gem aminophosphines were capable of mediating the coupling reaction at a loading of 1 mol%.

10.
Org Biomol Chem ; 14(46): 10848-10860, 2016 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-27805223

RESUMEN

Two methodologies for the formation of substituted amino[2.2]paracyclophane derivatives were developed. The first involves the direct amination of bromo[2.2]paracyclophanes with sodium azide. This permits the synthesis of simple mono- and disubstituted derivatives but fails to give sterically congested pseudo-gem derivatives. A 'one-pot' oxidation-Lossen rearrangement of [2.2]paracyclophane oximes provides access to a range of amino[2.2]paracyclophanes including the most efficient synthesis of the pseudo-gem planar chiral amino acid yet reported.

12.
J Med Virol ; 83(8): 1358-61, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21618551

RESUMEN

Vulval intraepithelial neoplasia is a precursor of vulval carcinoma, and is frequently associated with human papillomavirus (HPV) infection. Estimates of HPV prevalence in vulval intraepithelial neoplasia vary widely in the UK. The objective of this study was to assess HPV infection in a sample of women with vulval intraepithelial neoplasia, confirmed histologically, and determine the proportion of disease associated with HPV types targeted by prophylactic HPV vaccines. HPV infection was assessed in biopsies from 59 patients using the Greiner Bio-One PapilloCheck® DNA chip assay. Valid results were obtained for 54 cases. HPV infection was present in 43 of the 54 cases (79.6%: 95% CI 67.1-88.2%). The most common HPV types were HPV 16 (33/54: 61.1%), HPV 33 (8/54: 14.8%), HPV 6 (5/54: 9.3%), and HPV 42 (3/54: 5.6%). The mean age of HPV positive women was significantly less than the mean age of HPV negative women. This is the largest UK series of vulval intraepithelial neoplasia in which HPV type has been investigated, and 34/54 (63.0%, 95% CI: 49.6-78.6%) cases were associated with HPV 16/18, which are targeted by current prophylactic HPV vaccines.


Asunto(s)
Carcinoma in Situ/virología , Papillomaviridae/clasificación , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , Neoplasias de la Vulva/virología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Carcinoma in Situ/complicaciones , Femenino , Genotipo , Humanos , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Prevalencia , Reino Unido/epidemiología , Neoplasias de la Vulva/complicaciones
13.
Chem Commun (Camb) ; 47(1): 433-5, 2011 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-20865190

RESUMEN

A rapid and versatile method for the preparation of planar chiral [2.2]paracyclophane-derived pyridines and pyridine N-oxides is reported. The potential utility of these compounds in Lewis base catalysis is briefly introduced.


Asunto(s)
Bases de Lewis/química , Óxidos/síntesis química , Catálisis , Estructura Molecular , Óxidos/química , Compuestos Policíclicos/química , Piridinas/química , Estereoisomerismo
14.
Dalton Trans ; 39(15): 3687-94, 2010 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-20364463

RESUMEN

Two planar chiral heteroaryl monophosphines have been synthesised and studied. The phosphines are readily prepared from 4-imidazole[2.2]paracyclophane by selective deprotonation and reaction with the appropriate dialkylchlorophosphines. The planar chiral imidazole was constructed in four steps from readily available [2.2]paracyclophane. The 2-phosphino-N-[2.2]paracyclophanes were active in the Suzuki-Miyaura coupling of aryl bromides and chlorides. Coordination studies indicate P,N-chelation in the solid-state. These studies lay the foundations for asymmetric couplings.

15.
Beilstein J Org Chem ; 5: 9, 2009 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-19478964

RESUMEN

This paper describes a simple route to enantiomerically enriched [2.2]paracyclophane-4-thiol via the stereospecific introduction of a chiral sulfoxide to the [2.2]paracyclophane skeleton. The first synthesis of an enantiomerically enriched planar chiral benzothiazole is also reported.

16.
Org Biomol Chem ; 6(9): 1527-34, 2008 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-18421381

RESUMEN

[2.2]Paracyclophane is a fascinating molecule that offers great potential in a wide range of chemical disciplines. Currently, the synthesis of the majority of enantiomerically pure [2.2]paracyclophane derivatives is based on the resolution of a small number of starting materials or individual resolution procedures are developed for each new compound. The development of more general routes to these valuable compounds via the resolution of a common intermediate is discussed. Ultimately, it would be preferable to synthesise these valuable compounds without recourse to resolution and ideas for this rewarding goal are postulated.


Asunto(s)
Compuestos Policíclicos/síntesis química , Ciclización , Halogenación , Conformación Molecular , Compuestos Policíclicos/química , Estereoisomerismo , Sulfóxidos/química
17.
Beilstein J Org Chem ; 3: 39, 2007 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-17996034

RESUMEN

We have developed a general strategy for the synthesis of 2,5-syn disubstituted pyrrolidines that is based on the multi-faceted reactivity of the sulfone moiety and a 5-endo-trig cyclisation. This methodology was applied to the synthesis of indolizidine alkaloid monomorine I. Two factors were key to the success of this endeavour; the first was the choice of nitrogen protecting group whilst the second was the conditions for the final stereoselective amination step. Employing a combination of different protecting groups and an intramolecular reductive amination reaction we were able to prepare (+)-monomorine I in just 11 steps from commercially available D-norleucine in a completely stereoselective manner.

18.
Org Biomol Chem ; 3(21): 3873-6, 2005 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-16240000

RESUMEN

The ortho-lithiation of one diastereoisomer of 4-tert-butylsulfinyl[2.2]paracyclophane is the key step to the synthesis of a range of 4,5-disubstituted [2.2]paracyclophane derivatives.

19.
Chem Commun (Camb) ; (33): 4219-21, 2005 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-16100609

RESUMEN

A general strategy for the synthesis of enantiomerically pure 4-substituted [2.2]paracyclophanes from a common sulfoxide precursor is described.

20.
Chem Commun (Camb) ; (21): 2712-3, 2003 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-14649824

RESUMEN

The use of chiral sulfoxides as Lewis base catalysts in the allylation of aldehydes with allyltrichlorosilane is reported.

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