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Immunosuppressive drugs are widely used for the treatment of autoimmune diseases and to prevent rejection in organ transplantation. Gusperimus is a relatively safe immunosuppressive drug with low cytotoxicity and reversible side effects. It is highly hydrophilic and unstable. Therefore, it requires administration in high doses which increases its side effects. To overcome this, here we encapsulated gusperimus as squalene-gusperimus nanoparticles (Sq-GusNPs). These nanoparticles (NPs) were obtained from nanoassembly of the squalene gusperimus (Sq-Gus) bioconjugate in water, which was synthesized starting from squalene. The size, charge, and dispersity of the Sq-GusNPs were optimized using the response surface methodology (RSM). The colloidal stability of the Sq-GusNPs was tested using an experimental block design at different storage temperatures after preparing them at different pH conditions. Sq-GusNPs showed to be colloidally stable, non-cytotoxic, readily taken up by cells, and with an anti-inflammatory effect sustained over time. We demonstrate that gusperimus was stabilized through its conjugation with squalene and subsequent formation of NPs allowing its controlled release. Overall, the Sq-GusNPs have the potential to be used as an alternative in approaches for the treatment of different pathologies where a controlled release of gusperimus could be required.

Squalene has been used as a dietary supplement for a long history due to its potential cancer-preventive function. However, the mechanism has not been investigated in detail yet. Therefore, the aim of this study is to see if the plasma coenzyme Q10 (CoQ10) level will be altered by gavage of squalene and oxidosqualenes to rats. In the present work, a sensitive and simple high-performance analytical method based on ultra-high-performance liquid chromatography coupled with an Orbitrap mass spectrometry (UPLC-Orbitrap-MS) was developed for the quantification of CoQ10 in rat plasma. Coenzyme Q9 (CoQ9) was employed as the internal standard. CoQ10 was determined after acetonitrile-mediated plasma protein precipitation using UPLC-Orbitrap-MS in negative ion mode. Intragastric administration of squalene and the two squalene epoxides into rats once daily for several days elevated the level of CoQ10 in their plasma, but there was no significant difference between high-dose (286 mg/kg) and low-dose (143 mg/kg) groups. Intragastric administration of squalene once a day for 5 consecutive days and oxidosqualenes once a day for 3 consecutive days is necessary for reaching the steady-state level of CoQ10. Our present findings indicate that squalene and oxidosqualenes may be useful for stimulating the synthesis of CoQ10 in rats.

The disaccharide trehalose is an autophagy inducer, but its pharmacological application is severely limited by its poor pharmacokinetics properties. Thus, trehalose was coupled via suitable spacers with squalene (in 1:2 and 1:1 stoichiometry) and with betulinic acid (1:2 stoichiometry), in order to yield the corresponding nanolipid-trehalose conjugates 1-Sq-mono, 2-Sq-bis and 3-Be-mono. The conjugates were assembled to produce the corresponding nano-assemblies (NAs) Sq-NA1, Sq-NA2 and Be-NA3. The synthetic and assembly protocols are described in detail. The resulting NAs were characterized in terms of loading and structure, and tested in vitro for their capability to induce autophagy. Our results are presented and thoroughly commented upon.

Dioscorea zingiberensis is a perennial medicinal herb rich in a variety of pharmaceutical steroidal saponins. Squalene epoxidase (SE) is the key enzyme in the biosynthesis pathways of triterpenoids and sterols, and catalyzes the epoxidation of squalene in coordination with NADPH-cytochrome P450 reductase (CPR). In this study, we cloned DzSE and DzCPR gene sequences from D. zingiberensis leaves, encoding proteins with 514 and 692 amino acids, respectively. Recombinant proteins were successfully expressed in vitro, and enzymatic analysis indicated that, when SE and CPR were incubated with the substrates squalene and NADPH, 2,3-oxidosqualene was formed as the product. Subcellular localization revealed that both the DzSE and DzCPR proteins are localized to the endoplasmic reticulum. The changes in transcription of DzSE and DzCPR were similar in several tissues. DzSE expression was enhanced in a time-dependent manner after methyl jasmonate (MeJA) treatments, while DzCPR expression was not inducible.

Squalene-hopene cyclase (SHC) has been found to convert acyclic squalene into 6,6,6,6,5-fused pentacyclic triterpenes hopene and hopanol. The enzymatic reactions of squalene analogues bearing ethyl groups in lieu of methyl groups at positions C-6, C-10, C-15, and C-19 have been examined to investigate whether the larger ethyl substituents (a C1 unit increment) are accepted as substrates and to investigate how these substitutions affect polycyclization cascades. Analogue 6-ethylsqualene 19a did not cyclize, which indicates that substitution with the bulky group at C-6 completely inhibited the polycyclization reaction. In contrast, 19-ethylsqualene 19b afforded a wide spectrum of cyclization products, including mono-, bi-, tetra-, and pentacyclic products in a ratio of 6:6:1:2. The production of tetra- and pentacyclic scaffolds suggests that the reaction cavity for D-ring formation site is somewhat loosely packed and can accept the 19-ethyl group, and that a robust hydrophobic interaction exists between the 19-ethyl group and the binding site. In contrast to 19b, 10-ethylsqualene 20a and 15-ethylsqualene 20b afforded mainly mono- and bicyclic products, that is, the polycyclization cascade terminated prematurely at the bicyclic reaction stage. Therefore, the catalytic domains for the 10- and 15-methyl binding sites are tightly packed and cannot fully accommodate the Et substituents. The cyclization pathways followed by the ethyl-substituted substrates in the presence of SHC and lanosterol and β-amyrin synthases are compared.

Among other things, the present disclosure relates to designed oligonucleotides, compositions, and methods thereof. In some embodiments, provided oligonucleotide compositions provide altered splicing of a transcript. In some embodiments, provided oligonucleotide compositions have low toxicity. In some embodiments, provided oligonucleotide compositions provide improved protein binding profiles. In some embodiments, provided oligonucleotide compositions have improved delivery. In some embodiments, provided oligonucleotide compositions have improved uptake. In some embodiments, the present disclosure provides methods for treatment of diseases using provided oligonucleotide compositions.

The present disclosure pertains to the recognition that immune responses mediated by CpG oligonucleotides can be affected by the stereochemistry of modified internucleotidic linkages such as phosphorothioates. In some embodiments, the present disclosure relates to chirally controlled CpG oligonucleotide compositions comprising CpG oligonucleotides comprising multiple modified internucleotidic linkages such as phosphorothioate linkages, wherein the oligonucleotides comprise one or more CpG region motifs having defined stereochemistry patterns of chiral internucleotidic linkages. In some embodiments, CpG oligonucleotides comprising one or more CpG region motifs are capable of agonizing an immune response. In some embodiments, CpG oligonucleotides comprising one or more CpG region motifs are antagonistic. Methods for making and using chirally controlled CpG oligonucleotide compositions are also described. In some embodiments, no immune modulation is desired, and the present disclosure provides methods of identifying chirally controlled oligonucleotide compositions which have decreased immune modulation.

To examine how the sterics at the 23 position of (3S)-2,3-oxidosqualene 1 influence the polycyclization cascade in β-amyrin biosynthesis, substrate analogues substituted with an ethyl group (10, 11), a hydrogen atom (12, 13), or a propyl residue (14) at the 23 position were incubated with β-amyrin synthase. The bulkier ethyl group was accepted as a substrate, leading to formation of the β-amyrin skeleton (42, 43) without truncation of the multiple cyclization reactions. Analogue 13, possessing a hydrogen atom and an ethyl group at the 23E and 23Z positions, respectively, was also converted into the β-amyrin skeleton 45. However, the analogue lacking an ethyl group at the 23Z position (12) underwent almost no conversion, strongly indicating that an alkyl group must exist at the Z position. The cyclization of the analogue with a propyl substituent at the Z position (14) was poor. Analogue 15 possessing CH2OH at the 23E position afforded a new compound 47 in a high yield as a result of trapping of the final oleanyl cation. Conversely, 16 with 23Z-CH2OH afforded novel compounds 48-50 in low yields, which resulted from the intermediary dammarenyl and baccharenyl cations. Therefore, the hydrophobic interaction between the 23Z-alkyl group and its binding site (possibly via CH/π interaction) is critical for adopting the correct chair-chair-chair-boat-boat conformation and for the full cyclization cascade.

The use of an excess amount of tetraphenylphosphonium tetrafluoroborate in 1,1,1,3,3,3-hexafluoroisopropanol, which can stabilize the intermediate cation in the reaction, efficiently promoted epoxide-initiated cation-olefin polycyclization reactions with broad functional group tolerance and water and oxygen tolerance.

The present study reports the preparation of a novel class of squalene conjugates with paclitaxel, podophyllotoxin, camptothecin and epothilone A. The obtained compounds are characterized by a squalene tail that makes them able to self-assemble in water,

Two kinds of niobium(V)-silica catalysts for the selective epoxidation were synthesised by post-synthesis modification of non-ordered mesoporous silica supports, starting from niobocene dichloride via solvent-less organometallic precursor dry impregnation

We report the development of isotopic-labeled 13C diffusion-ordered NMR spectroscopy (DOSY) NMR with diffusion coefficient-formula weight (D-FW) analysis and its application in characterizing the aggregation state of methyllithium aggregates and complexes with several widely used diamines. Commercially available 13C-labeled benzene and several easily synthesized 13C-labeled compounds using 13C-labeled iodomethane as the isotopic source are developed as internal references for diffusion-formula weight analysis (D-FW). The technique greatly expands the applicability of DOSY D-FW analysis to a much wider variety of compounds because of isotopic labeling. These results reveal that methyllithium exists as a tetrasolvated tetramer in diethyl ether and exclusively as bis-solvated dimers with chelating diamines.

The C2-symmetric (-)-glabrescol was synthesized in two steps from (10S,11R)-dihydroxy-10,11-dihydrosqualene or squalene with 50% or 10% overall yields, respectively. These highly efficient and biomimetic syntheses employed a base-promoted middl

Figure Presented (+)-Omaezaklanol was synthesized in only three steps from racemic chlorohydrin 4 by Shi epoxidatlon followed by cascade cyclization and reduction.

A variety of epoxy polyene terpenes cyclize readily by confinement within zeolite NaY to form primarily products of monocyclization. The monocyclization pathway is highly predominant, irrespectively of the side chain of the epoxy terpene, while the monocyclic products possess regioselectively an exomethylenic double bond. The selective monocyclization in the case of epoxyfarnesyl acetate, epoxyfarnesylacetone or 2,3-epoxysqualene, provides a direct route to the synthesis of a variety of natural products, such as elengasidiol, farnesiferols B-D, achilleol A, camelliol C and to four farnesylacetone-derived metabolites isolated from the brown algae Cystophora monoliformis. The optical rotation of achilleol A derived from the cyclization of (S)-2,3-epoxysqualene matches with that of the natural product, thus the absolute configuration of achilleol A was established as 1S,3R. From the mechanistic point of view, the NaY-promoted cyclization of 9,10-epoxygeranylacetone, selectively deuterium labelled at the C-10 methyl group, is >97% stereoselective with respect to the topicity of the gem-dimethyl group. This result is in agreement with a concerted mechanism. Finally, we have proved through labelling experiments, for the first time, that the biomimetic transformation of epoxy polyene terpenes to 2,3,4-trimethylcyclohexanones upon acid catalysis is a highly stereoselective process. Thus, the less hindered gem-methyl group on the epoxide functionality becomes α- to the carbonyl in the final isomerized product.

Dimethyldioxirane (1a) and its trifluoro analog (1b) were employed to achieve selectively the direct transformation of squalene 2,3(S)-oxide and of squalene 2,3(R)-oxide into the corresponding 2,3(S);22(S),23-dioxide and 2,3(R);22(R),23-dioxide, respectively. These transformations were found to occur with convenient regio- and diastereoselectivity, providing easy access to the valuable dioxides metabolites. The powerful methyl(trifluoromethyl)dioxirane (1b) is the reagent of choice to achieve optimum yields of the target compounds.

To provide insight into the polycyclization mechanism of squalene by squalene-hopene cyclase (SHC) from Alicyclobacilus acidocaldarius, some analogs of nor- and bisnorsqualenes were synthesized including the deuterium-labeled squalenes and incubated with the wild-type SHC, leading to the following inferences. (1) The deprotonation reaction for the introduction of the double bond of the hopene skeleton occurs exclusively from the Z-methyl group on the terminal double bond of squalene. (2) 3R-Oxidosqualene was folded in a boat conformation for the A-ring construction, while the 3S-form was in a chair structure. (3) The terminal two methyl groups are indispensable both for the formation of the 5-membered E-ring of the hopene skeleton and for the initiation of the polycyclization cascade, but the terminal Z-methyl group has a more crucial role for the construction of the 5-membered E-ring than the E-methyl group. (4) Some of the novel terpene skeletons, 36,37, 39 and 40. were created from the analogs employed in this investigation.

To provide deep insight into the polycyclization reaction of squalene, some analogs were synthesized and incubated with the cell-free homogenates of the recombinant Escherichia coli encoding the wild-type squalene cyclase. The presence of C(6)-Me leads to an efficient polycyclization cascade. Substitution of the C(14)-H and the C(18)-H with a methyl group halted the polycylization reaction at the tricyclic ring stage having a 6/6/6-fused ring system and the tetracycle with a 6/6/6/6-fused ring, respectively, both of which were produced according to a Markovnikov closure. Replacement of the C(7)-H and the C(11)-H with a methyl group led to no cyclization. These results, in conjunction with our previous reports, indicated that the methyl positions are important for bringing to completion of the normal polycylization reaction and further demonstrated that the precise steric bulk size at the methyl positions of squalene is critical to the correct folding and the strong binding of the substrate to the squalene cyclase.

The synthesis of (E)- and (Z)-29-methylidyne-2,3-oxidosqualene derivatives is described starting from the C22 and C17 squalene aldehyde monobromohydrins. The conversion was achieved by means of a Wittig reaction, followed by desilylation of the terminal acetylene. For trisubstituted 1,3-enynes, preliminary alkylation with a suitable allyl bromide was performed. A new procedure for the synthesis of squalene aldehyde C27, C22 and C17 monobromohydrins is also described. Some of the new compounds behaved as inhibitors of pig liver and yeast oxidosqualene cyclase and were time-dependent inhibitors of the animal enzyme.

Squalene-hopene cyclase (matrix presented) Incubation of (6E,10E,14E,18E)-2,6,10,19,23-pentamethyl-tetracosa-2,6,10,14,18,22-hexaene with Alicyclobacillus acidocaldarius hopene cyclase afforded four products having two types of carbocyclic skeletons, i.e., two hopane products and two products having an unprecedented carbocyclic skeleton of 6/5 + 5/5 +6 pentacyclic and 6/5 + 5/5 tetracyclic ring systems. The former two hopane skeletons were formed from the bioconversion of C(15)-desmethylsqualene and the latter two skeletons from that of C(10)-desmethylsqualene.

Cationic cyclizations are among the most demanding reactions that have been catalyzed by antibodies. These studies provided valuable mechanistic insights while opening up the possibility of formation of steroidal carbon frameworks. However, they have involved substrates that contained an aryl sulfonate group adjacent to a primary carbon center not observed in natural cationic cyclization processes. This paper presents an extension of our earlier work, now focusing on substrates analogous to those seen in triterpene biosynthesis. Three antibodies, 15D6, 20C7, and 25A10, have been generated by immunization with an 4-aza-steroid aminoxide hapten (termed HA8) that initiate the cationic cyclization of an oxidosqualene derivative and catalyze the formation of ring A of the lanosterol nucleus at neutral pH. Antibody HA8-25A10 kinetically resolved its racemic substrates. Design of the substrate was based on a dual-anchor model for specific binding that consists of displaying a functional group at the head (epoxide trigger) and the tail (amide functionality) of the otherwise hydrophobic poly-ene chain. The assay involved solubilization of the substrates with 0.2% surfactant. No ring formation was detected in the absence of antibody catalyst. The uncatalyzed epoxide hydrolysis was slow and did not deprive the antibody of substrate. Observations in the field of enzymic poly-ene cyclizations suggest that subtle changes in the substrate structure may well lead to multi-ring formation under the influence of the current catalyst.

Three triterpenes having the 6/6/5-fused tri- and 6/6/6/5-fused tetracyclic skeletons were isolated from an incubation mixture of the mutated F601A enzyme, these products being in accordance with a Markovnikov closure. Successful trapping of the tricyclic

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The preparation and characterization of oxidosqualenes 3-(6R,7R), 3-(6S,7S), 4-(10R,11R), and 4-(10S,11S) is reported.Squalenediol 6 was converted into the corresponding mixture of (R)-Mosher ester 8 and 9, which were separated by semipreparative HPLC.Esters 8 and 9 were reduced to the chiral diols 6-(6R,7S) and 6-(6S,7R), respectively, which were finally converted into the corresponding epoxides 3-(6R,7R) and 3-(6S,7S).A similar procedure was used for the preparation of chiral epoxy derivatives 4-(10R,11R) and 4-(10S,11S) from esters 10 and 11, respectively.The determination of the absolute configuration of these epoxides was carried out by using the method reported by Ohtani et al. (J.Am.Chem.Soc. 1991, 113, 4092), which was adapted to the case of racemic mixtures from synthetic origin.For this purpose, the (R)-Mosher esters derived from the enantiomers of squalendiols 6 or 7 were used.The validity of this approach was confirmed by the absolute configuration found for the threo squalenediols 6-(6R,7R), 6-(6S,7S), 7-(10R,11R), and 7-(10S,11S) formed in the Sharpless asymmetric dihydroxylation of squalene (Crispino, G.A.; Sharpless, K.B.Tetrahedron Lett. 1992, 33, 4273).Results on the inhibitory activity of oxidosqualenes 3-(6R,7R), 3-(6S,7S), 4-(10R,11R), and 4-(10S,11S) using purified squalene epoxidase (SE) from pig liver showed that epoxide 3-(6S,7S) was the best inhibitor within the compounds assayed (IC 50 = 6.7 μM), although oxidosqualene 4-(10R,11R) also exhibited a moderate inhibitory activity (IC 50 = 25μM).The inhibition elicited by the epoxy derivative 3-(6S,7S) was competitive with respect to squalene (Ki = 2.7 μM).This activity is comparable to that reported for the most potent competitive SE inhibitors described so far.Finally, incubation of oxidosqualene 3-(6S,7S) with purified SE led to the formation of dioxidosqualene 22-(3S,6S,7S), whereas its regioisomer 23-(3S,18S,19S) was not detected.In contrast, incubation of epoxide 3-(6R,7R) under the same conditions affored a mixture of dioxides 22-(3S,6R,7R) and 23-(3S,18R,19R) in a 5:12 molar ratio.The fact that oxidosqualenes 3 and 4 have been found in nature, and our previous results showing that racemic dioxide 23 is a potent inhibitor of oxidosqualene-lanosterol cyclase in rat liver microsomes (Abad, J.L.; et al.J.Org.Chem. 1993, 58, 3991), confers a potential physiological relevance to the results reported herein.

19-Azasqualene 2,3-epoxide and its N-oxide, high-energy intermediate analogue inhibitors of 2,3-oxidosqualene (SO) cyclase were obtained by total synthesis.These compounds were designed to mimic the C-20 carbonium ion precursor of lanosterol formed during SO cyclization.The synthesis involved the preparation of C22squalenoid aldehyde epoxide through a new procedure and the reconstruction of the squalenoid chain bearing a nitrogen at C-19 (pro C-20). 19-Azasqulene 2,3-epoxide was active on SO cyclase from rat and pig liver with an IC50 of 1.5 μM in pig. while in SO cyc lases of yeast (S cerevisiae and C albicans) microsomes it was 20-30-fold less active.It was inactive on squalene epoxidase from rat and pig liver at the highest concentrations tested (100 μM). 2,3-oxidosqualane cyclase inhibitors/ epoxy azasqualanes/ hypocholesterolemic/ antifungals

Squalene was selectively degradated to tris-norsqualene, and this was converted into 1-fluoro, 1,1-difluoro, and 2-trimethylsilylmethyl analogues of squalene, and also into 2-cyanonorsqualene.These compounds were designed as potential inhibitors of fungal squalene epoxidase/epoxysqualene cyclase, but biological evaluation using five fungal pathogens revealed that none exhibited more than modest antifungal activity.

Epoxidation of C=C double bonds in terpenes is achieved by reaction with linoleic acid hydroperoxides (LOOH) exemplified with caryophyllene (3), methyl farnesoate (5) and squalene (8).Linoleic acid (9S)-hydroperoxide was obtained by reaction of linoleic acid (1) with lipoxygenase present in tomato homogenisate.When 18O2-labeled (9S)-LOOH (2) was used 18O was found in the terpene epoxide.While 3 is converted under physiological conditions regioselectivity in high yield into its 4,5-epoxide 4, the yield of epoxidized products from long-chain molecules, e.g. squalene (8), decreases strongly and no regioselectivity was observed. - Key Words: Terpenes/ Epoxides/ Linoleic acid derivatives/ Hydroperoxides/ Labeled compounds, 18O2

2,3-Epoxy-10-aza-10,11-dihydrosqualene, a high-energy intermediate analogue inhibitor of 2,3-xidosqualene (SO) cyclase was obtained by total synthesis.This involved the preparation of three main building blocks: (1) C17 squalenoid N-methylamine, (2) 3-(diphenylphosphinoyl)propanal, and (3) 5,6-epoxy-6-methylheptan-2-one.The final stages of the reconstruction of the 6E double bond were obtained by a Wittig-Horner reaction which was modified for poorly reactive systems.This compound was designed to mimic the C-8 carbonium ion formed during SO cyclization.Its inhibitory activity on various SO cyclases was evaluated and compared with the 6 Z isomer which has an unfavorable geometry.Only isomer 6 E, the carbocation analogue, was active on SO cyclases from rat liver, pig liver, S. cerevisiae, and C. albicans microsomes, with an I50 varying from 3 to 5 μM.Both E and Z isomers were inactive on squalene epoxidase at the higher concentrations tested.

Squalene was degraded to tris-norsqualene aldehyde, and this was converted into 2-fluoromethyl-, 2,2-difluoromethyl-, 2-trimethylsilylmethyl-analogues of squalene, and into 2-cyano-norsqualene.

In a search for potential "suicide" inhibitors of squalene epoxidase, a series of mono- and bifunctional squalenoid acetylenes and allenes was synthesized and their inhibitory activity was assayed in preliminary tests.Squalenoid acetylenes were obtained a

The stereospecific synthesis of squalenoid epoxide vinyl ethers with an isopentyloxy group is described.The synthesis involves the preparation of the C22 squalenoid aldehyde bromohydrin (15) by a new method via a one-step cleavage of lipophilic epoxides using periodic acid in diethyl ether, and the preparation of (1-isopentyloxyethyl)diphenylphosphine oxide (24).The structure of this compound has been confirmed by X-ray analysis.The configuration of vinyl ethers, synthesized using a Wittig-Horner reaction, has been determined by (13)C n.m.r.Biological results show that vinyl ethers (5) and (27) are competitive inhibitors of 2,3-oxidosqualene cyclase from rat liver.

Azasqualenes, bis-azasqualenes and derivatives, designed as inhibitors of squalene 2,3-epoxide cyclase, a key enzyme in sterol biosynthesis, were synthesized and their in vitro activities against a variety of yeasts, fungi, gram-positive and gram-negative bacteria were determined.The synthesis involves a new method of squalene degradation, together with an unusual procedure for the aminative reduction of lipophilic aldehydes.A study of the structure-activity relationship was attempted for different biological parameters: anti-bacterial and anti-fungal activities (MIC), inhibition of mycelial growth (GTT), surfactant activity (CMC) and membrane perturbation activity (induction of leakage in liposomes).

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