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α-Tocopheryl succinate (α-TS) and α-tocopheryloxyacetic acid (α-TEA) are potent inducers of apoptosis in cancer cells and efficient suppressors of tumors in experimental model cancer cell lines. They exhibit selective cytotoxicity against tumor cells and very limited or no toxicity toward nonmalignant cells. In the present work, a series of new α-tocopherol derivatives were synthesized as analogs of α-TS and α-TEA. The cytotoxic activity of obtained compounds was tested using three human cancer cell lines, including chronic lymphoblastic leukemia (CEM), breast adenocarcinoma (MCF7), cervical adenocarcinoma (HeLa), and normal human fibroblasts (BJ). The introduction of an alkyl substituent into the ether-linked acetic acid moiety in α-TEA increased anticancer activity. α-Tocopheryloxy-2-methylpropanoic acid with two additional geminal methyl groups was more active against CEM cells compared to α-TEA and non-toxic to normal cells. In order to acquire a deeper understanding of the biological activity of synthesized compounds, a molecular docking study was also conducted. Our research confirmed that vitamin E derivatives are interesting and valuable compounds in terms of their potential therapeutic use as anticancer agents. [ABSTRACT FROM AUTHOR]

This paper describes an efficient method for synthesis of new 1,2,3,4-tetrahydronaphthalene-2-carboxylic acids as carbacyclic analogs of trolox. Graphical abstract: [Figure not available: see fulltext.]. [ABSTRACT FROM AUTHOR]

A new synthetic route to 25-hydroxy-provitamin D 3 was elaborated. The synthesis consists of direct hydroxylation at C-25 of 7-dehydrocholesterol hetero Diels-Alder adducts. The adducts were prepared by [4 + 2] cycloaddition of azadienophiles to the steroidal diene. The hydroxylation reactions of adducts were carried out with different dioxiranes or with chromyl trifluoroacetate. The byproducts of these reactions were isolated and identified. The strengths and weaknesses of hydroxylation methods with different oxidizing agents were discussed.

A simple synthesis method of solanidane alkaloids from common steroidal sapogenins was developed. Previously described multi-step transformations of tigogenin to demissidine (8-12 steps) were shortened to four steps only. The key-step of the present synthesis was the epimerization at C25 of the lactam intermediate. Different approaches to this reaction, i. e., a classical one via enolate, and a chemoselective umpolung transformation, were thoroughly investigated. The epimerization step is unnecessary if the starting sapogenin has the same configuration at C25 as the target alkaloid because the configuration at C25 (either R or S) remains intact throughout the synthesis. Thus, the related solanidane alkaloids, 12β-hydroxy-25-epi-demissidine and 5-epi-demissidine, were synthesized in the three-step procedure with retention of configuration at this stereogenic center from rockogenin (25R-5α-sapogenin) or sarsasapogenin (25S-5β-sapogenin), respectively., (© 2023 Wiley-VCH GmbH.)

A concise synthesis of (16 S ,20 S )-3β-hydroxy-5α-pregnane-20,16-carbolactam from tigogenin via the corresponding lactone is described. The most efficient synthetic route consisted of the lactone ring-opening with aminoalane reagent followed by PDC or Dess-Martin oxidation. The oxo-amide obtained was subjected to cyclization with Et 3 SiH/TFA or Et 3 SiH/Bi(TfO) 3 . Alternately, the lactone was converted first to the oxo-acid, which was then subjected to the microwave-assisted reductive amination. N -Alkyl derivatives were also obtained in a similar way.

The validity of the chromane helicity rule correlating the sense of twist within the dihydropyran ring with the CD sign of the (1)Lb band observed at ca. 290 nm in their electronic circular dichroism (ECD) spectra is examined using a set of natural (S)-trolox derivatives. To investigate both the scope and the limitations of the rule a combination of ECD spectroscopy, especially the temperature dependence of the ECD spectra, single crystal X-ray diffraction analyses, and density functional theory (DFT) calculations was used. A thorough conformational analysis supported by the X-ray data led to the identification of predominant conformers. Then, a comparison of the experimental ECD spectra with the spectra simulated by TDDFT calculations allowed for a reasonable interpretation of the accumulated data. The results clearly indicated that to avoid the possibility of erroneous conclusions the chromane helicity rule should be used with great caution. This is likely related to the conformational flexibility of tested compounds by which conformers of different helicities can be produced. Therefore, based on the results presented here, it is strongly recommended that the conclusions derived from analysis of experimental data are supported with the appropriate theoretical computations.

The crystal structure of the title compound, C(14)H(17)NO(2), solved and refined against synchrotron diffraction data, contains one formula unit in an asymmetric unit. In the crystal, mol-ecules form right-handed helices located at the 2(1) screw axis parallel to the a-axis direction, generated by O-H⋯N hydrogen bonding between the hy-droxy group and carbonitrile group of an adjacent mol-ecule.

The crystal structure of the title compound, C(28)H(38)O(11), solved and refined against synchrotron diffraction data, contains two formula units in the asymmetric unit. In both mol-ecules, the dihydro-pyran ring along with its methyl substituents is disordered and adopts two alternative half-chair conformations. The occupancy of the major conformers of the two mol-ecules refined to 0.858 (5) and 0.523 (5).

The crystal structure of the title water-soluble analogue of vitamin E, trolox amide, C(14)H(19)NO(3), solved and refined against synchrotron diffraction data, contains two mol-ecules in the asymmetric unit. In both molecules, the heterocyclic ring is in a half-chair conformation. The crystal packing features a herring-bone pattern generated by N-H⋯O hydrogen bonds between the hy-droxy and amide groups. O-H⋯O hydrogen bonds also occur.