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Twenty-one phenolic compounds (1–21) including dihydrocinnamic acid, isoflavonoids, flavonoids, coumestans, pterocarpans, chalcones, isoflavan and isoflaven, were isolated from the roots of Glycyrrhiza pallidiflora Maxim. Phloretinic acid (1), chrysin (6), 9-methoxycoumestan (8), isoglycyrol (9), 6″-O-acetylanonin (19) and 6″-O-acetylwistin (21) were isolated from G. pallidiflora for the first time. Isoflavonoid acetylglycosides 19, 21 might be artefacts that could be produced during the EtOAc fractionation process of whole extract. Compounds 2–4, 10, 11, 19 and 21 were evaluated for their cytotoxic activity with respect to model cancer cell lines (CEM-13, MT-4, U-937) using the conventional MTT assays. Isoflavonoid calycosin (4) showed the best potency against human T-cell leukaemia cells MT-4 (CTD50, 2.9 μM). Pterocarpans medicarpin (10) and homopterocarpin (11) exhibit anticancer activity in micromolar range with selectivity on the human monocyte cells U-937. The isoflavan (3R)-vestitol (16) was highly selective on the lymphoblastoid leukaemia cells CEM-13 and was more active than the drug doxorubicin

A selective synthesis of 7‐ or 14‐nitrogen containing tricyclic diterpenoids was completed according to a strategy in which the key step was the catalyzed direct allylic amination of methyl 14α‐hydroxy‐15,16‐dihydroisopimarate with a wide variety of nitrogenated nucleophiles. It was revealed that the selectivity of the reaction depends on the nature of nucleophile. The catalyzed reaction of the mentioned diterpenoid allylic alcohol with 3‐nitroaniline, 3‐(trifluoromethyl)aniline, and 4‐(trifluoromethyl)aniline yield the subsequent 7α‐, 7β‐ and 14αnitrogen‐containing diterpenoids. The reaction with 2‐nitroaniline, 4‐nitro‐2‐chloroaniline, 4‐methoxy‐2‐nitroaniline, phenylsulfamide, or tert‐butyl carbamate proceeds with the formation of 7α‐nitrogen‐substituted diterpenoids as the main products.

A series of new analogs of combretastatin A-4 (CA-4, 1) with the A or B-ring replaced by a 3-oxo-2,3-dihydrofurocoumarin or a furocoumarin residue have been designed and synthesized by employing a cross-coupling approach. All the compounds were evaluated for their cytotoxic activity with respect to model cancer cell lines (CEM-13, MT-4, U-937) using conventional MTT assays. Structure-activity relationship analysis reveals that compounds 2, 3, 6–8 in which the (Z)-styryl substituent was connected to the 2-position of the 3-oxo-2,3-dihydrofurocoumarin core, demonstrated increased potency compared to 3-(Z)-styrylfurocoumarins 4, 5, 9–11. The methoxy-, hydroxyl- and formyl- substitution on the aromatic ring of the (Z)-styryl moiety seems to play an important role in this class of compounds. Compounds 2 and 3 showed the best potency against the CEM-13 cell lines, with CTD50 values ranging from 4.9 to 5.1 μM. In comparison with CA-4, all synthesized compounds presented moderate cytotoxic activity to the T-cellular human leucosis cells MT-4 and lymphoblastoid leukemia cells CEM-13, but most of them were active in the human monocyte cell lines U-937.

By oxidation of methyl lambertianate with potassium permanganate, the esters of 17-nor-8-ketoand 17-hydroxy-8,12-epoxy-labdadienic acids have been obtained. Reductive amination of the above carbonyl compounds and subsequent intramolecular aminomethylation of 17-nor-8(R)methylamino- and 17-methylamino-labdadienoates by formaldehyde leads to the formation of novel polycyclic compounds, which are derivatives of furoazocines and furoazonines.

The synthesis of the title compounds 1 by1:1condensationof Ar N S N SiMe3 2withSCl2 followed by intramolecular ortho-cyclization of each (Ar N S N S Cl) intermediate is complicated by further reaction of 1 with SCl2 to give Herz salts 3. With the 2:SCl2 ratio of 2:1, the formation of by-products 3 is reduced and novel compounds 1 are accessible. With ortho-I containing starting material 2j, the parent compound 1s is obtained as the result of an unex- pected I, not H, substitution. The rate of the 1C SCl2 reaction depends upon a substituent's position, and the minor 8-R isomers 1l,p (RD Br, I) are isolated for the first time from mixtures with the major 6-R isomers due to reduced reactivity toward SCl2. The synthesized compounds 1-3 are characterized by mul- tinuclear (including nitrogen) NMR and X-ray crys- tallography. According to the X-ray diffraction data, 1j (6-Br) and 1k (7-Br) derivatives are planar, whereas 1i (5-Br) and 1l (8-Br) are bent along the S1¢¢¢N4 line by»5 - and»4 - , respectively, and the 1r (7-OCH3) de- rivative is planar in contrast to the known 5-OCH3 isomer, which possesses a significantly folded hetero

The title reaction is highly regioselective, leading in both cases to 4,5,6,7,8,9-hexafluoronaphtho[1,2-c]-[1,2,5]thiadiazole (whose struture is confirmed by X-ray structure analysis) and 4,5,6,7,8,9-hexafluoronaphtho[2,3-c][1,2,5]thiadiazole in ∼94 : 6 ratio. The preferred direction of cyclization is consistent with final product thermodynamics as well as factors of kinetic control for orbital-controlled reactions (calculated by use of frontier MOs theory).