1,3 - Dipólusok képzése és azok cikloaddíciós reakciói a 13 alfa-ösztron sorban = Synthesis of 1,3 - dipoles and their cycloaddition reactions in the 13a-estrone series

A 13'- és 13'-ösztron sorba tartozó d-alkenil-szekoaldehidekből Schiff-bázisokat, oximokat, oximétereket és fenilhidrazonokat képeztünk, majd az így nyert bifunkciós vegyületeket továbbalakítottuk. A Schiff-bázisokból aza-Prins reakcióban 17a-aminofenil-D-homo-, míg ugyanezen alapanyagokból intramolekulás cikloaddícióban kondenzált vázas tetrahidrokinolin hibridvegyületeket nyertünk. Tanulmányoztuk továbbá a '-alkenil-oximok elektrofil reagensek hatására mutatott gyűrűs nitron képzési reakcióit, majd a nitronokat N-fenilmaleimiddel reagáltatva, sztereoszelektíven nyertünk kondenzált vázas aza-D-homo vegyületeket. Megfigyeltük, hogy a reakciókörülmények változtatásával az oximok ambidens nukleofilként viselkednek, és a kinetikailag kontrollált oxazepin-terméket közvetett úton, a nem szimmetrikus szteroid-dimer alkotórészeként sikerült izolálnunk. A '-alkenil-fenilhidrazonok PhSeBr-dal történő gyűrűzárása során sztereoszelektíven nyertünk gyűrűs imínium sókat, amelyek C=N kettős kötésének redukciója újszerű aza-D-homoszteroidokhoz vezetett. Előállítottunk továbbá szteroid-dipolarofileket is, majd ezen 13'-ösztránvázas endo-, illetve exociklusos kettős kötésű szteroidokat hidrazonoil-kloriddal reagáltattuk. A nitrilimin dipólus képzése in situ, heterogén vagy homogén katalízissel történt. Az endociklusos kettős kötésű szteroidok sztereoszelektíven két regioizomer kondenzált vázas pirazolint, míg az exociklusos vegyületek szelektíven egy izomer spiropirazolint adtak. | Novel tetrahydroquinoline and N-aryl D-homo derivatives in the 13'-estrone series were synthetized, starting from the delta-alkenyl secoaldehyde and substituted anilines. The chemoselectivity of the cyclization reactions depended upon the nature of the substituents in the anilines. Halogen-induced formation of 13'- and 13'-estrone nitrones and their subsequent 1,3-dipolar cycloaddition reactions with N-phenyl maleimide stereoselectively furnished condensed heterocyclic D-homosteroids. Electrophile-induced cyclization of steroidal '-alkenyl oximes and oxime ethers and subsequent reduction of the nitrones led to new halogenated or selenylated N-hydroxy- or N-benzyloxy-aza-D-homo-estrones. Starting from a 13?-D-secoestrone oxime ether, dimers were isolated in intermolecular cycloaddition of the cyclic nitrone to the C=N double bond of the oxazepine intermediates. Novel delta-alkenyl phenylhydrazones were synthesized in both estrone series. Electrophile-induced cyclizations of hydrazones with phenylselenyl bromide furnished cyclic iminium salts, hydride reduction of which led to novel aminophenyl-substituted derivatives. Effective syntheses of ','-unsaturated ketones as C=C dipolarophiles were carried out in the 13'-estrone series. The 1,3-dipolar cycloadditions of 15,16',-unsaturated ketones with nitrilimines stereoselectively furnished two regioisomers of new condensed pyrazolines, but the cycloadditions to the 16-methylene-17-ketones furnished only one spiropyrazoline

Synthesis of fluorescent dyes for bioimaging

Super-resolution fluorescence microscopy offers good sensitivity and high temporal resolution for characterizing cellular structures and biomolecules. Red-emittig fluorescent dyes are ideal fluorophores for biomolecule labeling, due to reduced absorbance and autofluorescence of cells in far-red or near-red window. Here we synthesized novel fluorescent dyes based on carbopyronine core. The dyes were synthesized from two fragments based on cyclocondensation and/or Friedel-Crafts alkylation strategies

Synthesis of red-emitting fluorophores

Understanding the mechanism of action of biologically active compounds is of great interest in medicine, including cancer research. Chemical labeling of molecules, i.e. making them "visible" under the right conditions, is a widespread and intensively researched field of science. The fluorescent labeling of compounds offers several advantages over other methods. It might be considered as an environmentally friendly alternative to radioisotope labeling. It is highly important that fluorophores used in biomedical applications meet certain criteria, including high photostability, good cell permeability and stability under physiological conditions. However, the accessibility of the fluorophores is often limited owing to their high price and complex synthetic strategies. Here we synthesized aza-BODIPY fluorophores, which are red-emitting altervatives to BODIPY derivatives. The syntheses were carried out considering the principles of green chemistry. One-pot and/or microwave-assisted syntheses were performed in order to minimize the number of reaction steps and time and use of solvents

Szelektív antitumor hatású ösztronszármazékok szintézise

Living organisms compete for survival and reproduction, whereupon the fittest live and thrive and the weakest fail and some cases even die. This battle for life acts on different levels, causing individuals of distinct species as well as individuals of the same species to compete over a variety of limiting resources such as food, breeding sites and mates. An important form of competition is driven by sexual conflict and often occurs when reproductive strategies between males and female diverge. These occur because there are differences in the evolutionary interests of the sexes over, for example, optimal reproductive rate, gamete size and parental investments. This has led to the evolution of different strategies to alter or overcome the manipulation of one sex by other, while maintaining a base line level of cooperation sufficient to ensure successful reproduction. This sexual conflict is an important evolutionary process as it can drive rapid evolutionary change. The manipulation of one sex by the other through molecular interactions has been illuminated in studies using the fruit fly Drosophila melanogaster. Males tend to maximize their chances at fatherhood by releasing both sperm and semen inside the female’s body during mating. The effects of semen proteins can benefit both sperm and eggs, but intriguingly they can also favour the interests of males whilst generating costs in females, resulting in sexual conflict. In Drosophila melanogaster, the female body has been the battlefield of sexual conflict, as semen proteins exert their effects in females after mating. This manipulation by males through molecular interactions can inflict substantial physical and physiological costs of mating in females. One enigmatic seminal fluid protein the ‘Sex Peptide’, generates strikingly diverse changes in female physiological and reproductive behaviour. Sex Peptide triggers remarkable female post mating responses including altered fertility, immunity, libido, eating and sleep patterns, by the activation of diverse sets of genes. In many studies of the molecular mechanisms of female manipulation via the effects of Sex Peptide, genetic variation is minimised in order to clearly delineate biological functions. However, to understand the evolutionary processes and dynamics that characterise Sex Peptide mediated interactions between males and females, it is important to study this genetic variation. With high-throughput sequencing technologies that have provided resources such as >200 fully sequenced DGRP lines (Drosophila Genome Reference Panel), we traced the impact of the enigmatic Sex Peptide on the fruitfly genome. In this thesis I performed an in-depth investigation of the phenotypic and genomic differences among 30-32 DGRP lines, with respect to male release of, and female responses to, Sex Peptide. I measured phenotypic variation for Sex Peptide release in males; and in females the phenotypic variation in immune responses, egg laying, receptivity and longevity in response to Sex Peptide receipt. I compared these phenotypic post-mating responses to those of females that mated to males with a null-allele for Sex Peptide, to distinguish the specific response to Sex Pepetide. I mapped these phenotypes to genomic variation using Genome Wide Association Studies and conducted functional characterizations on the genomic variation identified

A molecular understanding of d-homoestrone-induced G2/M cell cycle arrest in HeLa human cervical carcinoma cells

2-Methoxyestradiol (ME), one of the most widely investigated A-ring-modified metabolites of estrone, exerts significant anticancer activity on numerous cancer cell lines. Its pharmacological actions, including cell cycle arrest, microtubule disruption and pro-apoptotic activity, have already been described in detail. The currently tested d-ring-modified analogue of estrone, d-homoestrone, selectively inhibits cervical cancer cell proliferation and induces a G2/M phase cell cycle blockade, resulting in the development of apoptosis. The question arose of whether the difference in the chemical structures of these analogues can influence the mechanism of anticancer action. The aim of the present study was therefore to elucidate the molecular contributors of intracellular processes induced by d-homoestrone in HeLa cells. Apoptosis triggered by d-homoestrone develops through activation of the intrinsic pathway, as demonstrated by determination of the activities of caspase-8 and -9. It was revealed that d-homoestrone-treated HeLa cells are not able to enter mitosis because the cyclin-dependent kinase 1-cyclin B complex loses its activity, resulting in the decreased inactivation of stathmin and a concomitant disturbance of microtubule formation. However, unlike 2-ME, d-homoestrone does not exert a direct effect on tubulin polymerization. These results led to the conclusion that the d-homoestrone-triggered intracellular processes resulting in a cell cycle arrest and apoptosis in HeLa cells differ from those in the case of 2-ME. This may be regarded as an alternative mechanism of action among steroidal anticancer compounds

Szteránvázas vegyületek szintézise = Synthesis of Steroid Compounds

Az érdeklődésünk 2003-2005 között a cisz C/D gyűrűs 3-metoxi-, illetve a 3-benziloxi-ösztra-17-on származékok felé fordult. A kívánt 13α-D-szeko-ösztron-aldehid előállítására a legjobbnak a 16-jódmetil származékok bizonyultak, amelyek a kívánt 13α-szeko-ösztron-aldehiddé voltak alakíthatók. - Az aldehid csoport, valamint az olefin oldallánc lehetőséget adott egy Prins típusú ciklizációra. Ennek eredményeként a hattagú D-gyűrűs 3-metoxi-, illetve 3-benziloxi-D-homo-ösztronhoz jutottunk. - A 13β-D-szeko-ösztron-aldehid Grignard reakcióval, majd az azt követő intramolekulás Heck reakcióval hét-, nyolc-, illetve kilenctagú D-gyűrűt tartalmazó ösztron származékokhoz vezetett. - A 13α-, és a 13β-D-szeko-ösztron-aldehidek intramolekulás reakcióval gyűrűs nitronokká alakultak, amelyek N-fenil-maleinimiddel 1,3-dipoláros cikloaddícióval halogént tartalmazó D-homo-ösztron heterociklusokhoz vezettek. -Egy 9,13-áthidalt D-szeko-ösztron alkaloid típushoz jutottunk a 13β-szeko-ösztron-aldehid anilinnel, és szubsztituált anilinekkel, Lewis-sav jelenlétében végzett reakciójával. Az új D-szeko-ösztron-izokinuklidin keletkezése1,5-hidrid-ion vándorlással értelmezhető. - Új utat találtunk a transz-3β-hidroxi-16,17-szeko-pregna-5,17(20)-dién-16-al előállítására. Az így nyert szeko-szteroidban a formil csoport és a telítetlen oldallánc alkalmassá teszi a szteránvázhoz kondenzált heterociklusok kialakítását. | During the research period 2003-2005 we were interested in compounds with an inverted configuration at C-13, i.e. derivatives of 13α-estrane-17-on-3-ethers containing a cis junction of rings C and D. With the aim of preparing the 13α-D-seco-estrone aldehyde, the 16-iodomethyl derivatives were the starting materials for the fragmentation. - The presence of the olefinic moiety and the formyl group makes the molecules suitable for intramolecular Prins-type reaction. The result is the 3-methoxy-, and 3-benzyloxyestrone containing a six-membered ring D. - A new type of steroids with seven-, eight-, or nine-membered D-ring have been synthesized from 13β-D-seco-estrone aldehyde derivative by a Grignard and an intramolecular Heck reaction. - Starting from the 13α-, and 13β-D-seco-estrone aldehyde by 1,3-dipolar cycloaddition reactions with N-phenylmaleinimide stereoselectively furnished halogen-containing condensed heterocyclic D-homosteroids. - Unique 9,13-bridged D-seco-estrone alkaloids have been synthesized starting from 13β-seco-estrone aldehyde with aniline in the presence of Lewis acids. - A new synthetic route was developed for the preparation of trans-3β-hydroxy-16,17-seco-pregna-5,17(20)-dien-16-al. - Starting from the trans-3β-acetoxy-16,17-seco-pregna-5,17(20)-dien-16-al and using aniline with BF3.OEt2, different tetrahydroquinoline derivatives via Diels-Alder reaction were formed

Selective antiproliferative effect of C-2 halogenated 13α-estrones on cells expressing Organic anion-transporting polypeptide 2B1 (OATP2B1)

Organic anion-transporting polypeptide 2B1 (OATP2B1) is a multispecific transporter mediating the cellular uptake of steroids and numerous drugs. OATP2B1 is abundantly expressed in the intestine and is also present in various tumors. Increased steroid hormone uptake by OATP2B1 has been suggested to promote progression of hormone dependent tumors. 13 alpha-estrones are effective inhibitors of endogenous estrogen formation and are potential candidates to inhibit proliferation of hormone dependent cancers. Recently, we have identified a variety of 13 alpha/beta-estrone-based inhibitors of OATP2B1. However, the nature of this interaction, whether these inhibitors are potential transported substrates of OATP2B1 and hence may be enriched in OATP2B1overexpressing cells, has not yet been investigated. In the current study we explored the antiproliferative effect of the most effective OATP2B1 inhibitor 13 alpha/beta-estrones in control and OATP2B1-overexpressing A431 carcinoma cells. We found an increased antiproliferative effect of 3-O-benzyl 13 alpha/beta-estrones in both mock transfected and OATP2B1-overexpressing cells. However, C-2 halogenated 13 alpha-estrones had a selective OATP2B1-mediated cell growth inhibitory effect. In order to demonstrate that increased sensitization can be attributed to OATP2B1-mediated cellular uptake, tritium labeled 2-bromo-13 alpha-estrone was synthesized for direct transport measurements. These experiments revealed increased accumulation of [H-3]2-bromo-13 alpha-estrone due to OATP2B1 function. Our results indicate that C-2 halogenated 13 alpha-estrones are good candidates in the design of anti-cancer drugs targeting OATP2B1

Cytotoxic effect of 13α-estrane derivatives on breast, endometrial and ovarian cancer cell lines

Hormone-dependent cancers such as breast, uterine, and ovarian cancers account for more than 35% of all cancers in women. Worldwide, these cancers occur in more than 2.7 million women/year and account for 22% of cancer-related deaths/year. The generally accepted mechanism for the pathophysiology of estrogen-dependent cancers is estrogen receptor-mediated cell proliferation associated with an increased number of mutations. Therefore, drugs that can interfere with either local estrogen formation or estrogen action via estrogen receptors are needed. Estrane derivatives that have low or minimal estrogenic activity can affect both pathways. In this study, we investigated the effect of 36 different estrane derivatives on the proliferation of eight breast, endometrial, and ovarian cancer cell lines and the corresponding three control cell lines. Estrane derivatives 3 and 4_2Cl showed a stronger effect on the endometrial cancer cell lines KLE and Ishikawa, respectively, compared with the control cell line HIEEC, with IC50 values of 32.6 microM and 17.9 microM, respectively. Estrane derivative 4_2Cl was most active in the ovarian cancer cell line COV362 compared to the control cell line HIO80 with an IC50 value of 3.6 microM. In addition, estrane derivative 2_4I showed a strong antiproliferative effect on endometrial and ovarian cancer cell lines, while the effect on the control cell line was slight or absent. The addition of halogen at carbon 2 and/or 4 in estrane derivatives 1 and 2 increased the selectivity for endometrial cancer cells. Overall, these results suggest that single estrane derivatives are efficient cytotoxic agents for endometrial and ovarian cancer cell lines, and thus potential lead compounds for drug development. © 2023 The Author