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Diels-Alder and 1,3-dipolar cycloaddition reactions of selected guanidine cycloaddends
No full textVeliki broj prirodnih organskih spojeva sadržava gvanidinsku funkcionalnost, a među najpoznatijima su nukleotid gvanin i aminokiselina arginin. Njihova raznolikost u prirodi je golema, spojevi mogu biti strukturno vrlo kompleksni, policiklički s višestrukim podjedinicama koje sadrže gvanidin kao strukturni motiv. Gvanidinska skupina zanimljiva je zbog svoje gotovo planarne strukture te visoke bazičnosti. Derivati gvanidina primjenjuju se stoga u baznoj katalizi, kao receptori za anione te kao aktivna mjesta u molekulskim preklopnicima. U ovome radu sustavno su istražene mogućnosti priprave novih derivata gvanidina koristeći Diels- Alderove i 1,3-dipolarne cikloadicijske reakcije. Ispitani su cikloadicijski reagensi za uvođenje gvanidinske funkcionalnosti; gvanilirani derivati pirola, izoindola, azidi i izatini. Pripravljen je i novi reagens za dobivanje antracen-2,3-arina. Istražena je sposobnost kompleksiranja organskih aniona s pripravljenim spojevima sa slobodnom gvanidinskom funkcionalnošću.A large number of natural organic compounds contain the guanidine functionality, among the most well-known being the nucleotide guanine and the amino acid arginine. Their diversity in nature is immense – these compounds can be structurally very complex, polycyclic, with multiple subunits that contain guanidine as a structural motif. The guanidine group is interesting due to its nearly planar structure and high basicity. Guanidine derivatives are therefore used in base catalysis, as receptors for anions, and as active sites in molecular switches. This work systematically investigates the possibilities of synthesizing new guanidine derivatives using Diels-Alder and 1,3-dipolar cycloaddition reactions. Cycloaddition reagents for the introduction of guanidine functionality were examined, including guanylated derivatives of pyrrole, isoindole, azides, and isatins. A new reagent for the synthesis of anthracene-2,3-aryne was also prepared. The potential for complexation of organic anions with the synthesized compounds containing a free guanidine functionality was also explored
HARD-BOTTOM POLYCHAETE FAUNA IN THE INFRALITTORAL ALGAL BIOCOENOSIS OF THE EASTERN ADRIATIC SEA
No full textRazred mnogočetinaša (Polychaeta) predstavlja jednu od najbrojnijih i najraznolikijih skupina organizama u bentoskim zajednicama čvrstih morskih dna te se smatra reprezentativnom skupinom za procjenu ekološkog stanja nekog područja. U ovom istraživanju, analizirani su sastav i sezonske razlike faune mnogočetinaša čvrstih dna u različitim zajednicama alga koje su se razvijale u različitim ekološkim uvjetima. Zbog širokog raspona ekoloških uvjeta, za područje istraživanja odabran je širi akvatorij grada Splita. Istraživanje je provedeno sezonski, u jesen i proljeće 2018. godine. Zajednice mnogočetinaša i alga na čvrstim dnima uzorkovane su destruktivnom metodom (s površine 400 cm2) sa sedam postaja na dubini od 1 m. Na svim postajama u razdoblju od godine dana mjereni su salinitet i temperatura te je određena koncentracija hranjivih soli. Određeno je 89 vrsta mnogočetinaša koje su pripadale u 24 porodice i 145 svojti bentoskih makroalga. Na temelju rezultata istraživanja utvrđeno je kako su se zajednice mnogočetinaša razlikovale sastavom između postaja s različitim zajednicama alga koje su se razvijale u različitim ekološkim uvjetima, kao i između istraživanih sezona. Najveća bioraznolikost i gustoća zajednica mnogočetinaša pronađena je na postajama s najvećom bioraznolikošću i pokrovnošću krupnih, strukturalno kompleksnih svojti alga, koje su se nalazile u blizini otvorenog mora, dok je najmanja bioraznolikost zabilježena na postajama u blizini antropogenih izvora onečišćenja. Bioraznolikost mnogočetinaša pokazala se kao dobar pokazatelj ekološkog stanja. U sklopu ovog istraživanja utvrđena je prisutnost strane vrste mnogočetinaša Lysidice collaris. Endemska sredozemna vrsta Streblosoma nogueirai prvi je put zabilježena na istočnoj strani Jadranskoga mora, dok su sredozemne vrste Syllis kabilica i Syllis tyrrhena prvi put zabilježene u Jadranskom moru.Polychaetes constitute one of the most abundant and taxonomically diverse groups within benthic communities inhabiting hard substrates and are widely regarded as key bioindicators for evaluating the ecological condition of marine habitats. In this study, the composition and seasonal differences of polychaete fauna on hard bottoms in various algal communities that developed under different ecological conditions were analyzed. Due to the wide range of ecological conditions, the broader area of the city of Split was selected as the research area. The research was conducted seasonally, in autumn and spring of 2018. Polychaete and algal communities on hard bottoms were sampled destructively (from a surface area of 400 cm²) at seven stations at a depth of 1 meter. Throughout the year, salinity and temperature were measured at each station, along with nutrient levels. A total of 89 polychaete species belonging to 24 families and 145 taxa of benthic macroalgae were identified. The composition of polychaete communities was found to differ between stations with different algal communities shaped by varying environmental conditions, and also between the two sampling seasons. The highest biodiversity and abundance of polychaete communities were found at stations with the greatest biodiversity and coverage of large, structurally complex algal taxa, located near the open sea, while the lowest biodiversity was recorded at stations near anthropogenic sources of pollution. Polychaete biodiversity proved to be a good indicator of ecological status. Within this study, the presence of the alien polychaete species Lysidice collaris was confirmed. The endemic Mediterranean species Streblosoma nogueirai was recorded for the first time in the eastern Adriatic Sea, while the Mediterranean species Syllis kabilica and Syllis tyrrhena were recorded for the first time in the Adriatic Sea
Struktura i sastav drvenaste podzemne biomase geoksila u travnjacima i otvorenim šumama južne i središnje Angole
No full textGeoxyles, despite their ecological importance in relation to biodiversity, carbon storage, and
disturbance resistance, are often overlooked due to their life strategy of keeping most of their
biomass underground. This study fills a research gap by examining the structure and composition
of woody belowground biomass (BGB) distribution patterns in geoxyle grassland and open
woodland vegetation types across south-central Angola, using eight different sampling sites to
capture environmental variability. A direct destructive sampling approach was employed to
accurately measure BGB and corresponding carbon stocks and investigated the influence of
environmental factors on BGB allocation, with a particular emphasis on soil analysis.
The results revealed that disturbances and climate seasonality were crucial for geoxyle occurrence
and high levels of recorded BGB, while soil fertility and seasonality were identified as the primary
drivers of belowground geoxyle functional types and their diversity.
The findings of this study will contribute to a better understanding of BGB dynamics in geoxylerich ecosystems and provide valuable information for conservation and climate change mitigation
efforts. The importance of further research in this area is highlighted, as the destruction of these
habitats due to agriculture and land-use changes could result in significant losses of BGB and
contribute to global warming.Unatoč ekološkoj važnosti u kontekstu bioraznolikosti, skladištenja ugljika i otpornosti na
poremećaje, geoksili su često zanemarivani zbog svoje životne strategije držanja glavnine biomase
ispod površine zemlje. Ova studija popunjava prazninu u istraživanju ispitivanjem strukture i
sastava distribucijskih uzoraka drvenaste podzemne biomase (BGB) u vegetacijskim tipovima
geoksilnih travnjaka i otvorenih šuma diljem južno-središnje Angole, koristeći osam različitih
mjesta uzorkovanja za obuhvaćanje varijabilnosti okoliša. Pristup izravnog destruktivnog
uzorkovanja korišten je za precizno mjerenje BGB-a i odgovarajućih zaliha ugljika, te je ispitan
utjecaj okolišnih čimbenika na distribuciju BGB-a, s posebnim naglaskom na analizu tla.
Rezultati su pokazali da su učestalost poremećaja i klimatska sezonalnost bili ključni za pojavnost
geoksila i visoke razine zabilježenog BGB-a, dok su plodnost tla i sezonalnost identificirani kao
primarni pokretači podzemnih geoksilnih funkcionalnih tipova i njihove raznolikosti.
Nalazi ove studije pridonijet će boljem razumijevanju dinamike BGB-a u ekosustavima bogatim
geoksilima i pružiti relevantne informacije u svrhu konzervacije i ublažavanja klimatskih
promjena. Naglašena je važnost daljnjih istraživanja u ovom području jer bi uništavanje navedenih
staništa zbog intenziviranja poljoprivrede i promjene načina korištenja zemljišta moglo rezultirati
značajnim gubicima BGB-a i pridonijeti globalnom zatopljenju
THE EFFECT OF SGLT2 INHIBITORS ON MARKER OF MYOCYTE STRESS (NTproBNP) IN TYPE 2 DIABETES
No full textU ovoj prospektivnoj opservacijskoj studiji procjenjivani su kardiovaskularni učinci
inhibitora kotransportera natrij-glukoza 2 (SGLT2) kod bolesnika sa šećernom bolesti tipa 2 u
kojih je postojala loša glukoregulacija na monoterapiji metforminom te im je bila potrebna
intenzifikacija terapije (SGLT2 inhibitori ili inhibitori dipeptidil-peptidaze 4). Na početku i
nakon šest mjeseci dodatne terapije obavljena je krvna analiza te fizikalni i ehokardiografski
pregled. Nisu nađene značajne razlike između skupina u biomarkerima miocitnog i
oksidacijskog stresa, upale te krvnom tlaku, dok su se indeks tjelesne mase, trigliceridi,
aspartat-aminotransferaza, mokraćna kiselina, E/E’, deceleracijsko vrijeme i sistolički tlak u
plućnoj arteriji značajno snizili, a udarni volumen i indeksirani udarni volumen te lipoprotein
visoke gustoće, hematokrit i hemoglobin značajno povisili u skupini na SGLT2 inhibitorima.
Iz navedenog proizlazi da mehanizmi djelovanja SGLT2 inhibitora podrazumijevaju brze
promjene u odnosu masnog i nemasnog tkiva, metaboličkim parametrima, zatim smanjeno
srčano opterećenje te poboljšanje dijastoličkih i sistoličkih parametara srčane funkcije.This prospective observational study evaluated the cardiovascular effects of sodium
glucose cotransporter 2 inhibitors (SGLT2i) in patients with type 2 diabetes and poor
glucoregulation on metformin who needed additional therapy (SGLT2i or dipeptidyl peptidase4 inhibitors in the control group). At the beginning and after six months of additional therapy,
laboratory analysis, physical and echocardiographic examination were performed. There were
no significant differences between the two groups in terms of biomarkers of myocyte and
oxidative stress, inflammation and blood pressure. Body mass index, triglycerides, aspartate
aminotransferase, uric acid, E/E’, deceleration time, and systolic pressure in the pulmonary
artery significantly decreased, while stroke volume, and indexed stroke volume as well as highdensity lipoprotein, hematocrit, and hemoglobin, significantly increased in the group on
SGLT2i. According to the results, SGLT2i mechanisms of action obviously comprise rapid
changes in body composition and metabolic parameters, reduced cardiac load, and
improvement in diastolic and systolic heart parameters
Synthesis of mannosylated desmuramyl peptide derivatives with a ferrocene subunit at α-position od D-isoglutamine
No full textU sklopu ovog diplomskog rada sintetizirana su tri nova manozilirana derivata desmuramil-
peptida (DMP-a) s lipofilnom ferocenskom podjedinicom vezanom na α-kraj D-izoglutamina
pri čemu je varirana duljina ugljikovodične razmaknice između ferocena i peptidnog dijela
molekule. Aminoferocen je pripravljen uklanjanjem Boc-zaštitne skupine sa zaštićenog
aminoferocena, dok su aminometilferocen i (2-aminoetil)ferocen pripravljeni redukcijom
pripadnog amida, odnosno nitrila. Kao polazni peptid korišten je zaštićeni dipeptid L-alanil-D-
glutaminska kiselina (Boc-L-Ala-D-Glu(OBn)). Na α-kraj glutaminske kiseline DMP-a
amidnom vezom vezani su ferocenski amini s različitim brojem metilenskih skupina između
amino-skupine i ferocenske podjedinice reakcijom kondenzacije pomoću EDC/HOBt i HBTU
metode. Nakon uklanjanja Boc-zaštitne skupine s amino-skupine L-alanina u kiselim uvjetima,
amidni ferocenski derivati desmuramil-peptida vezani su amidnom vezom s benzilima
zaštićenom manoznom podjedinicom preko C2 razmaknice u istim uvjetima amidacije.
Posljednji korak u sintezi bio je uklanjanje benzilnih zaštitnih skupina sa šećernog dijela
molekule i benzilog estera s bočnog ogranka D-izoglutamina postupkom katalitičke
hidrogenolize čime su uspješno sintetizirane ciljne molekule kojima se ispituje adjuvantski
učinak.In this diploma thesis, three new mannosylated derivatives of desmuramyl-peptide (DMP) were
synthesized with a lipophilic ferrocene subunit bonded to the α-end of D-isoglutamine, whereby
the length of the hydrocarbon spacer between ferrocene and the peptide part of the molecule
was varied. Aminoferrocene was prepared by removing the Boc-protecting group from
protected aminoferrocene, while aminomethylferrocene and (2-aminoethyl)ferrocene were
prepared by reduction of the corresponding amide and nitrile. The protected dipeptide L-alanyl-
D-glutamic acid (Boc-L-Ala-D-Glu(OBn)) was used as starting peptide. Ferrocene amines with
a different number of methylene groups between the amino group and the ferrocene subunit are
attached to the α-end of the glutamic acid of DMP via amide bond obtained by condensation
reaction using EDC/HOBt and HBTU methods. After removal of the Boc-protecting group
from the amino group of L-alanine under acidic conditions, amide ferrocene derivatives of
desmuramyl-peptide are bound by an amide bond with benzylated mannose subunit via the C2
spacer under the same amidation conditions. The last step in the synthesis was the removal of
the benzyl protecting groups from the sugar part of the molecule and the benzylic ester from
the D-isoglutamine side branch by the catalytic hydrogenolysis process in the end target
molecules were successfully obtained and where then tested for adjuvant activity
Ground beetle assemblages (Coleoptera, Carabidae) as indicators of succession in the Trstenik bog
No full textCretovi su specifična močvarna staništa na kojima često glavnu ulogu imaju mahovine. Opstanak creta Trstenik ugrožen je zbog sukcesije vegetacije i isušivanja creta. U ovom su istraživanju kao indikatori promjena na cretu korišteni trčci (Carabidae). Ciljevi istraživanja bili su odrediti razlike u sastavu i strukturi zajednica trčaka na tri staništa na cretu Trstenik (središnjem i sukcesijskom dijelu creta te šumskom rubu), odrediti utjecaj okolišnih čimbenika na prostornu raspodjelu trčaka te definirati mjere očuvanja creta. Trčci su sakupljani metodom lovnih posuda od lipnja do listopada 2021. godine. Ukupno su sakupljene 44 vrste i 1551 jedinka trčaka. Bogatstvo vrsta, brojnost jedinki te indeksi raznolikosti i ujednačenosti zajednica trčaka bili su najmanji u središtu creta, ali se nisu statistički značajno razlikovali od parametara u sukcesijskom dijelu creta, dok su na šumskom rubu zabilježene statistički značajno više vrijednosti u odnosu na ostala istraživana staništa. Na cretu su najveći utjecaj na sastav zajednica trčaka imali povećana zastupljenost prizemnog sloja rašća i povišene vrijednosti temperature tla te, osobito u središnjem dijelu creta, povišena vlažnost i pH vrijednost tla, a na šumskom rubu povećana zastupljenost sloja drveća. Rezultati istraživanja upućuju na uznapredovali proces sukcesije u središnjem dijelu creta, no pronalazak indikatorskih vrsta trčaka ukazuje na postojanje uvjeta tipičnih za cretna staništa te su predložene mjere za obnavljanje staništa.Peat bogs are specific wetland habitats where mosses often play an important role. The Trstenik peat bog is threatened by vegetation succession and drying of the peat bog. In this study, ground beetles (Carabidae) were used as indicators of habitat changes. The objectives of this study were: i) to determine differences in the composition and structure of ground beetle communities in three habitats on the Trstenik peat bog, ii) to determine the influence of environmental factors on the spatial distribution of ground beetles, iii) to define peat bog conservation measures. Ground beetles were collected using pitfall traps. A total of 44 species and 1551 individuals were collected. All measured indices of ground beetle communities were lowest in the central part of the bog but did not differ significantly from the parameters in the successional part. Conversely, significantly higher values were recorded at the forest edge compared to the other two studied habitats. In the peat bog, the greatest impact on the composition of ground beetle communities had the increased presence of the herb layer and soil temperature values, and, particularly in the central part, increased soil moisture and pH. At the forest edge, the abundance of the tree layer played a significant role. The results of the study indicate progressive vegetation succession in the central part of the peat bog, but the discovery of indicator ground beetle species suggests the existence of typical peat bog conditions. Therefore, measures for habitat restoration are proposed
Phenotypic changes in Asellus aquaticus (Isopoda, Crustacea) as a result of exposure to darkness and to pharmacological modulators
No full textSlatkovodni jednakonožni rakovi vrste Asellus aquaticus naseljavaju površinska i podzemna staništa u kojima poprimaju različite fenotipove. Fenotipska plastičnost, sposobnost genoma da proizvede različite fenotipove uslijed djelovanja okoliša, je potencijalni mehanizam kojim se površinske populacije prilagođavaju podzemlju. Poznato je da epigenetski mehanizmi imaju važnu ulogu u odgovoru genoma na okoliš. Stoga sam u ovom radu istražila kako mrak, najbitnija karakteristika podzemlja, te farmakološki modulatori, djeluju na preživljenje i fenotip vrste Asellus aquaticus. Koristila sam bisfenol A (BPA; endokrini i epigenetički disruptor), 5-azacitidin (inhibitor metilacije DNA), radicicol (inhibitor proteina HSP90) i natrij butirat (inhibitor histon deacetilaza). Jedinke su izložene otopinama farmakoloških modulatora u periodu od tjedan dana, dio u potpunom mraku, a dio na fotoperiodu svjetlo-tama uz pripadajuće kontrolne skupine u vodi. Kontrolne skupine u mraku su bile manje pigmentirane te imale dulje antene od kontrolnih skupina na svjetlu. Jedinke u eksperimentalnim grupama su imale dulje antene uslijed djelovanja 5-azacitidina i natrij butirata, pigmentiranije su kada ih se izloži 5-azacitidinu, a manje pigmentirane u otopini BPA. Inhibicija proteina Hsp90 radicicolom dala je varijabilne fenotipove, ali ne statistički značajne promjene. Zaključno, endokrino i/ili epigenetičko djelovanje BPA, metilacija DNA, promjene strukture kromatina uslijed ostalih farmakoloških modulatora uključeni su u promjene fenotipova kod ovih rakova.Asellus aquaticus is a freshwater isopod, which inhabits surface and cave habitats expressing different phenotypes. Phenotypic plasticity, the genome's ability to produce different phenotypes in response to differing environments, is a potential mechanism of surface-dwellers’ adaptation to caves and epigenetic mechanisms often play a crucial role in the genome's response to the environment. Here, I investigated the effects of darkness, a key characteristic of caves, and pharmacological modulators on survival and phenotype of Asellus aquaticus. I used bisphenol A (BPA, endocrine and epigenetic disruptor), 5-azacytidine (DNA methylation inhibitor), radicicol (Hsp90 protein inhibitor), and sodium butyrate (histone deacetylase inhibitor). Individuals were exposed to pharmacological modulators for a week, some in complete darkness and others in light-dark photoperiod, alongside respective control groups in water. Dark-exposed group exhibited reduced pigmentation and longer antennae compared to light-dark controls. Individuals in the experimental groups exhibited longer antennae when exposed to 5-azacytidine and sodium butyrate; increased pigmentation with 5-azacytidine; and decreased pigmentation in the BPA solution. Inhibition of Hsp90 protein using radicicol resulted in statistically insignificant phenotypic changes. In conclusion, the endocrine and/or epigenetic effects of BPA, DNA methylation and changes in chromatin structure due to other chemicals, are involved in the phenotypic changes observed in these isopods
Application of metagenomic esterases for environmentally friendly degradation of polylactic acid
No full textPolimliječna kiselina (PLA) je biorazgradiv polimer čija su termička i mehanička obilježja slična masovno korištenoj plastici problematičnoj za zbrinjavanje. Biorazgradivosti i fizikalna svojstva čine PLA kandidatom za proizvodnju plastike koja se može razgraditi na okolišno prihvatljiv način. Enzimi koji razgrađuju PLA, za prihvatljivu okolišnu i industrijsku razgradnju, spadaju u skupinu α/β-hidrolaza. Trenutno je identificiran mali broj hidrolaza s aktivnošću prema PLA, a jednu od najvećih posjeduje nedavno otkriveni enzim MGS0156. U ovom diplomskom radu proizvedeni su MGS0156, njegov mutant i novi, do sada neokarakterizirani homolog, pronađen pretragom metagenomskih baza podataka. Hidrolitička aktivnost enzima prema PLA provjerena je u agaroznom gelu i slobodnoj suspenziji. Ovdje je prvi put pokazana aktivnost novog metagenomskog enzima prema PLA, koja se pokazala značajno većom od većine aktivnosti zabilježenih u literaturi. Računalnim metodama utvrđeno je da oba enzima imaju mobilni poklopac, identificirane su aminokiseline veznog mjesta s najvećim doprinosom vezanju supstrata i potencijalne mete za mutacije.Polylactic acid (PLA) is a biodegradable polymer with thermal and mechanical properties like those of widely used plastics with problematic disposal. Its biodegradability and physical properties make PLA a candidate for environmentally friendly plastic production. PLA-degrading enzymes used for environmentally friendly and industrial degradation, belong to the α/β-hydrolase group. A small number of PLA-hydrolases is identified, with one of the greatest activities belonging to a recently discovered MGS0156. Here, MGS0156, its mutant and a new, previously uncharacterized homologue discovered in metagenomic databases were produced. The hydrolytic activity towards PLA was tested in an agarose gel and a suspension. The hydrolytic activity of the new metagenomic enzyme was demonstrated for the first time and was found to be significantly higher than most activities documented in the literature. Using computational methods, it was found that both enzymes contain a mobile lid, binding site amino acids with the largest contribution to substrate binding were identified as well as potential mutation target
Systematization of places and forms of consumption of the LGBT communities in the City of Zagreb
No full textNa kontinuumu između autentičnosti i homonormativnosti, u disertaciji se analiziraju obrasci funkcioniranja i reprodukcije mjesta ružičaste potrošnje u Zagrebu. Istraživanje je utemeljeno na mješovitoj metodologiji s ciljem nadilaženja nedostataka pojedinačne primjene samo kvalitativnih ili samo kvantitativnih metoda. Ustanovljena je rezidencijalna LGBT jezgra u Zagrebu koja ujedno čini prostorni okvir pojave mjesta ružičaste potrošnje. Istovremeno propitkujući i održavajući normativnost urbanog prostora, mjesta ružičaste potrošnje čine dio heteronormativnoga statusa quo. Naglašena homonormativna obilježja, naročito u potrošačkom sistemu zabave – ključnom za uprostorivanje ružičaste potrošnje – limitiraju njihov emancipacijski potencijal. Naime, favoriziraju homoseksualnost i tradicionalne rodne identitete, (p)održavaju rodne uloge, promiču kult mladosti i mladolikosti te privilegiraju pojedince višeg socioekonomskog statusa. Dob, seksualnost i socioekonomski status identificirani su kao ključne varijable koje objašnjavaju ružičastu potrošnju, a razlike obrazaca potrošačkog ponašanja unutar LGBT zajednice pokazale su se većima od razlika između LGBT osoba i osoba heteroseksualne orijentacije.On the continuum between authenticity and homonormativity, the dissertation analyses the functional and reproductive patterns of pink consumption places in Zagreb. The research is based on a mixed methodology with the aim of overcoming the deficiencies of the individual application of only qualitative or only quantitative methods. The LGBT residential core in Zagreb was identified. Within this core, pink consumption places were also detected. These places simultaneously challenge and maintain the normativity of urban space, and are thus part of the heteronormative status quo. Clearly visible homonormative features, especially in the entertainment consumer system – the key to the spatialization of pink consumption – limit their emancipatory potential. Namely, they favour homosexuality and traditional gender identities, support and maintain gender roles, promote the cult of youth and youthfulness, and privilege those of higher socioeconomic status. Age, sexuality, and socioeconomic status were identified as key variables in explaining pink consumption, and differences in consumption patterns within the LGBT community were found to be greater than differences between LGBT people and people of heterosexual orientation
Thermodynamics of steroid complexation reactions with cyclodextrins and cucurbit[7]uril
No full textU ovom je radu istražena termodinamika inkluzije androsterona, androstandiona i testosterona te triju žučnih soli – natrijeva litokolata, deoksikolata i kolata u β- i γ‑ciklodekstrin te kukurbit[7]uril u vodi. U svim istraženim sustavima nastali su stabilni kompleksi (log K° > 3,5) što je kod heptamernih receptora posljedica isključivo negativne ΔrH°, a γ-ciklodekstrina i pozitivne ΔrS°. Trans‑izomeri steroida s β‑ciklodekstrinom tvore komplekse stehiometrije 1 : 1 i 1 : 2 (steroid : β-ciklodekstrin), dok je u slučaju žučnih soli opažen nastanak isključivo kompleksa stehiometrije 1 : 1. Afinitet γ‑ciklodekstrina prema žučnim solima veći je nego afinitet β-ciklodekstrina, a vidljivo je i da se stabilnost nastalih kompleksa smanjuje s povećanjem broja hidroksilnih skupina u strukturi žučnih soli. Unatoč izrazito negativnim vrijednostima ΔrCp°, standardne reakcijske Gibbsove energije za kompleksiranje androsterona i natrijeva kolata s γ-ciklodekstrinom se ne mijenjaju značajno s temperaturom (temperaturna entalpijsko‑entropijska kompenzacija).The thermodynamics of inclusion of androsterone, androstanedione and testosterone, as well as three bile salts – sodium lithocholate, deoxycholate, and cholate in β-, γ-cyclodextrin and cucurbit[7]uril was investigated in water. In all cases stable complexes were formed (log K° > 3,5). The reactions were enthalpy driven in case of heptameric receptors while the inclusion within γ-cyclodextrin was both enthalpically and entropically favourable. The trans‑isomers form 1 : 1 and 1 : 2 (steroid :
β-cyclodextrin) stoichiometric complexes, whereas bile salts form only 1 : 1 complexes. The affinity of γ‑cyclodextrin towards bile salts is higher compared to β-cyclodextrin and the stability of complexes with both cyclodextrins decrease with increasing number of hydroxyl groups in the bile salt structure. Despite considerably negative ΔrCp° values, the ΔrG° for the reaction of androsterone and sodium cholate with γ‑cyclodextrin does not change apreciably with the temperature (temperature enthalpy‑entropy compensation)