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A three component condensation of aromatic amine, aldehyde, and cyclopentadiene with subsequent N trifluoroacetylation leads to 4 and 4,8 substituted N trifluoroacetyl 3a,4,5,9b tetrahydro 3H cyclopenta[c]quinolines. Ozonation of the double bond in the latter produced the corresponding isomeric stable ozonides having (1R*,4S*,5aR*,6S*,11bR*) configuration and differing in inversion at the carboxamide nitrogen atom.

The 6-oxo group in 2,3 : 20,22-di-O-isopropylidene derivatives of 20-hydroxyecdysone and its 24,25/25,26-anhydro analog is reduced with NaBH 4 -CeCl 3 in a stereoselective fashion to afford the corresponding 6α-alcohols. In the first case, the reaction is accompanied by dehydration to give Δ 14 -bond. Reduction of the same substrates with NaBH 4 or LiAlH 4 in the absence of CeCl 3 leads to mixtures of 6α-and 6β-hydroxy derivatives, the latter prevailing. In all cases, epimerization at C 5 occurs.

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Introduction. The proximity of mining enterprises to settlements contributes to the pollution of the soil cover with heavy metals. Crops grown in garden plots accumulate chemical elements and are an intermediate link in the “soil - plant - human” chain. Purpose of the work. Assessment of the level of anthropogenic load on the territory adjacent to the mining enterprise, based on the study of the translocation of metals in the soil - plant system. Materials and methods. For the purpose of hygienic assessment of the chemical composition of the soil and vegetable products grown on it, the content of 7 microelements was determined by atomic absorption spectrometry. With the help of the coefficient of concentration of a chemical substance (Kc) and the total indicator of pollution (Zc), the level of chemical contamination of soils was determined. Using the total coefficient of anthropogenic load (Ka.n. = ∑Ci/PDUi), the territory was ranked according to the contamination of vegetables with toxic elements. The rate of accumulation of metals by vegetable crops was assessed by the coefficient of biological absorption (Ax) and the index of biochemical activity of the species (BAS). Results. The soil cover in the district is contaminated with a complex of metals, the content of gross forms of which exceeds the MPC by up to 1.9 times, mobile - up to 4.6 times. At a distance of up to 5 km around the mining enterprise, the maximum indicators of the total soil pollution (Zc = 44-65) have been established. Lead and zinc are elements of “biological accumulation” for all types of studied vegetable products grown in the zone of influence of the mining enterprise; cadmium is additionally concentrated in beets and carrots, and nickel in carrots. In vegetable samples, exceeding the permissible levels of cadmium and lead was noted. The most significant accumulation of heavy metals was found in the southern, southeastern, northern and northwestern directions from emissions. Conclusion. To eliminate the toxic effects of heavy metals in vegetables produced in the zone of influence of mining enterprises, it is recommended to include additional monitoring of nickel and zinc content in the social and hygienic monitoring system.

E)-Oximes derived from 20-hydroxyecdysone diacetonides and 7,8-dihydro analog were converted into the corresponding lactams (6-oxo-5a-aza-5a-homo derivatives) via Beckmann rearrangement. 14,15-Anhydro-20-hydroxyecdysone (Z)-oxime under analogous conditions (reaction with p-toluenesulfonyl chloride in acetone in the presence of Na 2 CO 3 ) gave rise to 20-hydroxyecdisone 20,22-acetonide (Z)-O-tosyloxime which did not undergo Beckmann rearrangement.Oximes are widely used in organic synthesis, and they exhibit diverse biological activity [1]. In the recent years, interest in oximes of the steroid series considerably increased [2,3]. This interest was stimulated primarily by the isolation of steroidal oximes from the marine sponges Cynachyrella alloclada and S. apion [4]. which, like their synthetic analogs [5], turned out to effectively inhibit aromatase (the key enzyme in the biosynthesis of estrogens) and attracted attention as potential antitumor agents [6]. Ecdysteroid oximes and their chemical properties have been studied poorly. We previously reported on the synthesis of 20-hydroxyecdisone oxime and the corresponding diacetonide [7].In the present work we succeeded in effecting Beckmann rearrangement of (E)-oximes II and V derived from 20-hydroxyecdysone and its 7,8-dihydro analog with a view to transform the ecdysteroid B ring into seven-membered lactam ring, a fragment intrinsic to azabrassinosteroids [8].By treatment of 20-hydroxyecdysone diacetonide I with hydroxylamine hydrochloride in pyridine we obtained a mixture of the corresponding (E)-and (Z)-oximes II and III (Scheme 1) [7]. The oximation of 7,8-dihydro-20-hydroxyecdysone diacetonide IV under analogous conditions gave (E)-oxime V (Scheme 2). When the oximation product of 7,8-dihydro analog IV was treated with a solution of potassium hydroxide in ethanol, we obtained 14,15-anhydro-7,8-dihydro-20-hydroxyecdysone diacetonide (E)-oxime VI. An attempt to reduce the latter into 7,8-dihydro-14-deoxy-20-hydroxyecdysone diacetonide oxime by catalytic hydrogenation over Raney nickel resulted in the formation of 7,8-dihydrostachysterone B diacetonide VII (Scheme 3). The 13 C NMR spectrum of VII was fairly similar to the spectrum of 7, 8-dihydrostachysterone B 20,22-acetonide [9], and some differences were related to the presence of an additional O,O′-isopropylidene protective group at positions 2 and 3 of compound VII.The structure of oximes V and VI was confirmed by the 1 H and 13 C NMR spectra. The signals were assigned using one-( 1 H, 13 C, APT) and two-dimensional correlation techniques (COSY, HSQC, HMBC). In the 13 C NMR spectra of oximes V and VI, the α-methylene carbon atom (C 7 ) resonated in a stronger field (δ C 26.18 and 26.16 ppm, respectively) than the C 5 atom (CH, δ C 42.28 and 42.48 ppm), indicating their syn (C 7 ) and anti (C 5 ) orientation with respect to the N-OH group. This means that oximes V and VI have E configuration [7, 10].Oximes of the ecdysteroid series did not undergo Beckmann rearrangement under conditions of acid catalysis. ...

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