Synthesis of ammonium salts ofO-substitutedN-nitrohydroxylamines

Ammonium salts ofO-substitutedN-nitrohydroxylamines were synthesized by nitration ofO-substitutedN-benzoyl- orp-nitrobenzoy1hydroxylamines followed by treatment of the reaction products with an alcohol solution of ammonia.Translated fromIzvestiya Akadernii Nauk. Seriya Khimicheskaya, No. 1, pp. 132–134, January, 1996.     

Dinitramide and its salts

N,N-Dinitro derivatives of alkylurethanes, benzamide, andp-toluenesulfamide were synthesized for the first time. Their reactions with ammonia afforded the ammonium salt of dinitramide in 44–85% yields.For part 9, seeIzv. Akad. Nauk. Ser. Khim., 1996, 451 [Russ-Chem. Bull., 199645, 433 (Engl. Transl.)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 908–912, April, 1996.     

Dinitramide and its salts

Dinitramide readily adds to acrolein, methyl vinyl ketone, and phenyl vinyl ketone, but not to acrylonitrile or methyl acrylate. Treatment of dinitro compounds (O₂N)₂NCH₂CH₂COR (R = H, Me, Ph, OMe) with bases results in dinitramide salts in 66–83 % yields.For part 1, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1264–1266, July, 1994.     

Synthesis of potassium salts ofO-substitutedN-nitrohydroxylamines

Potassium salts of O-substitutedN-nitrohydroxylamines were synthesized by nitration of O-substituted.N-acetylhydroxylamines followed by treatment of the reaction products with potassium methoxide.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 178–179, January, 1994.     

1-Acyldeoxyvasicinone salts as effective intermediate C-and N-acylating agents for alkaloids and amino acids

The reaction of deoxyvasicinone with acid chlorides of aliphatic (acetylbromide) and aromatic (benzoyl-, o-, p-methoxy-, p-nitrobenzoylchlorides) acids was studied. It was shown that 1-deoxyvasicinone salts were formed at room temperature; α-aroyloxymethylidenedeoxyvasicinones, in the presence of triethylamine at 80–85°C. It was found that acid chlorides cause 1-acyldeoxyvasicinone salts to transform into α-hydroxy-or α-aroyloxyarylidenedeoxyvasicinones, which indirectly confirmed their acylating properties. It was found that 1-acyldeoxyvasicinone salts were effective acylating agents for alkaloids (cytisine, 1,2-dihydrodeoxyvasicinone) and amino acids (glycine, β-alanine, α-aminobutyric acid) and can be used to acylate primary and secondary aliphatic and heterocyclic amines. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 585–589, November–December, 2006.     

Dinitramide and its salts

The dinitramide anion shows ambident properties. Its reactions with alkylating reagents give rise toN- orO-alkylated products or their mixtures. The reactions of alkylated products with bases were studied.For the previous communication, see V. A. Shlyapochnikov, G. I. Oleneva, N. O. Cherskaya, O. A. Luk'yanov, V. P. Gorelik, O. V. Anikin, and V. A. Tartakovsky,Izv. Akad. Nauk, Ser. Khim., 1994, 1610 [Russ. Chem. Bull., 1994,43, No. 11 (Engl. Transl.)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1775–1778, October, 1994.     

Alkylation of salts ofN-nitrohydroxylamines with chloromethylnitramines

The reactions of Ag-salts ofN-nitmhydroxyumines withN-methyl-N-chloromethylnitramine afford mainly products ofO-alkylation, whereas the reactions of the corresponding Li-, Na-, K-, Mg-, and NH₄-sals in the presence of tetrabutylammonium (TBAB) give mainly products ofN-alkylation. The reactions of the corresponding. NH₄-salts with bis-(chloromethyl)nitramine in the presence of TBAB lead solely to products ofO-alkylation. Increasing in the amount of TBAB results in the appearance of theN-isomer.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1740–1744, July, 1996.     

ipso- and tele-Substitution in reactions of 3-chloro-1-ethyl-2-R-pyrazinium salts with C-nucleophiles

The reactions of 2,3-dichloro- and 3-chloro-1-ethyl-2-morpholinopyrazinium tetrafluoroborates with compounds containing the active methylene group were studied. The reactions with malonodinitrile and cyanoacetic ester afford products of ipso-substitution at position 2, while 1,3-dicarbonyl compounds produce products of tele-substitution of the Cl atom at the C(3) atom due to the attack of a nucleophile to position 6 of the pyrazine cycle.     

Study of alkaloids of the Siberian and Altai flora. 10. Synthesis of N(20)-deethyllappaconitine derivatives

Efficient procedures were developed for N-deethylation of lappaconitine to give N(20)-deethyllappaconitine. Alkyl derivatives of N(20)-deethyllappaconitine, including labeled lappaconitine, and N(20)-acetoxy-N(20)-deethyllappaconitine were prepared for the first time. The assignments of the signals for the carbon atoms in the ¹³C NMR spectra of lappaconitine and related lappaconine were refined using ¹³C—¹³C 2D INADEQUATE and 2D ¹³C—¹H correlation experiments.     

Reactions of α-pentafluorophenylpyrylium salts with hydroxylamine

The reactions of α-pentafluorophenylpyrylium salts with hydroxylamine in ethanol afford isoxazoline derivatives and/or pyridine N-oxides depending on the steric characteristics of the substituent in the second α position. The structure of 2-hydroxy-2-pentafluorophenyl-4-phenyl-2,3,5,6,7,8-hexahydroquinoline 1-oxide, which was synthesized by the reaction of 2-pentafluorophenyl-4-phenyl-5,6,7,8-tetrahydrobenzopyrylium perchlorate with NH₂OH, was established by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 402–407, February, 2008.     

Study of alkaloids of the Siberian and altai flora

A number of known allied diterpene alkaloids were isolated fromDelphinium retropilosum Sambuk, a species growing in the Altai Territory. The main one was methyllycaconitine, possessing valuable pharmacological properties. For Part 1, see Ref. 1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 800–804, April, 1999.     

The reaction of salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides with dihalomethanes

Methylene-bis[N′-oxydiazene-N-(β-hydroxyalkyl)N-oxides] were synthesized by the reaction of salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides with diahalomethanes. The effect of the nature of the starting reagents and the reaction condtions on the yields of the target compounds was studied. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2266–2269, November, 1998.     

Preparation ofN-nitrohydroxylamines by substitutive nitration

Interaction of Na- or K-salts ofN-acetyl-N-methylhydroxylamines with aryl or aryl halides results in correspondingO-substitutedN-acetyl-N-methylhydroxylamines. Nitration of these compounds by nitronium salts or dinitrogen pentoxide results inO-substitutedN-methyl-N-nitrohydroxylamines.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 239–241, January, 1996.     

Study of alkaloids of the Siberian and Altai flora

Lappaconitine and N-deacetyllappaconitine derivatives containing bromine and iodine atoms in the aromatic moiety were synthesized. The Heck cross-coupling of these halides with ethyl acrylate or 2-methyl-5-vinylpyridine afforded new olefinated lappaconitine derivatives. Dedicated to the memory of Academician V. A. Koptyug on the occasion of the 75th anniversary of his birth. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1038–1044, June, 2006.     

Alkylation of salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides with alkyl halides and dimethyl sulfate

Salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides, RCH(OH)CH₂N(O)=NO⁻ M⁺ (R=Me, Prⁱ, or Bu^t; and M=Li, Na, K, Ag, NH₄, or Me₄N), were prepared. Their alkylation with alkyl halides R′X (X=Cl, Br, or I) and dimethyl sulfate was studied. Generally, alkylation afforded mixtures ofN-(β-hydroxyalkyl)-N′-alkoxydiazeneN-oxides RCH(OH)CH₂N(O)=NOR′ andO-alkyl-N-(β-hydroxyalkyl)-N-nitrosohydroxylamines RCH(OH)CH₂N(NO)OR′. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1996–2001, October, 1998.     

Vinamidinium salts of N-substituted aminoacetic acids

Formylation of N-phthaloylglycine with the POCl3-DMF system afforded N,N,N′, N′-tetramethyl-2-(N-phthaloyl)vinamidinium perchlorate (2). X-ray diffraction study showed that molecule 2 is planar and contains two equivalent nitrogen atoms in the three-carbon vinamidinium fragment. Salt 2 undergoes transamination with primary aromatic amines to give the corresponding bis-azomethines. The reactions with hydrazines produce substituted 4-aminopyrazoles. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 832–835, May, 2006.     

Croomine- and tuberostemonine-type alkaloids from roots of Stemona tuberosa and their antitussive activity

Three new croomine-type Stemona alkaloids, tuberocrooline (1), 10-hydroxycroomine (2), and dehydrocroomine (3), and four new tuberostemonine-type alkaloids, tuberostemoline (4), tridehydrotuberostemonine (5), 9α-bisdehydrotuberostemonine (6), and 9α-bisdehydrotuberostemonine A (7), along with ten known constituents, were isolated from the roots of Stemona tuberosa collected from Yunnan province. The structures of the new compounds were established on the basis of one- and two-dimensional NMR spectra and other spectroscopic studies. The antitussive activity of the major alkaloids was tested using the citric acid-induced guinea pig cough model. Croomine (8) exhibited a dose-dependent inhibition of coughing with an ID₅₀ value of 0.18 mmol/kg.     

季铵盐插层蒙脱土及其去除海洋卡盾藻的研究

利用插层法制备了5种季铵盐改性的蒙脱土,通过FTIR、XRD和DTG等表征表明5种季铵盐已成功插入蒙脱土中;随后以中国典型赤潮藻海洋卡盾藻(Chattonella marina)为研究对象,考察了5种季铵盐改性蒙脱土的除藻效果。发现以双溴化十四烷基二甲基乙基溴化铵改性的蒙脱土在用量为8mg·L-1时,24h内对海洋卡盾藻的去除率最高,可达100%,而未改性蒙脱土在相同条件下除藻率仅为5.64%;除藻效果与除藻剂的结构有密切关系,在官能团相同时,链长数为14的脂肪族季铵盐除藻率最高,24h可达67.03%;在链长数相同时,含吡啶官能团的季铵盐比脂肪族季铵盐除藻率高,24h为33.62%,且随时间延长明显提高。渗溢性评估实验显示,改性蒙脱土经72h浸泡后表观插层率从71.9%降低到69.6%,表明除藻剂在水体中基本不释放。     

New mesoionic systems of azolopyridine series 2. Synthesis,structures, and biological activity of 2-aminothiazolo[3,2-<Emphasis Type="Italic">a</Emphasis>]pyridinium salts and thiazolo[3,2-<Emphasis Type="Italic">a</Emphasis>]pyridinium 2-imidates

A new procedure was developed for the synthesis of 2-aminothiazolo[3,2-a]pyridinium salts 8 by the reaction of 2-halo-N-phenacylpyridinium salts with KSCN. The anion compositions of salts 8 were studied by ion chromatography. Acylation of salts 8 afforded representatives of the previously unknown bicyclic mesoionic thiazolo[3,2-a]pyridinium 2-imidate system 9. The three-dimensional structures of 2-amino-3-(p-bromobenzoyl)thiazolo[3,2-a]pyridinium thiocyanate and N-trifluoroacetyl-3-(p-nitrobenzoyl)thiazolo[3,2-a]pyridinium 2-imidate were established by X-ray diffraction analysis.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 226–232, January, 2005.     

Ammonium salts from polymer-bound N-hydroxysuccinimide as solid-supported reagents for EDC-mediated amidations

New ammonium and alkylammonium salts derived from a polymeric N-hydroxysuccinimide (P-HOSu) have been prepared and used for the amidation of carboxylic acids and amino acids mediated by 1-ethyl-3-(3′-dimethylamino-propyl)carbodiimide hydrochloride (EDC). These polymer-supported ammonium salts afforded the corresponding amides in good yield, without detectable α-racemization and with easy recovery of the P-HOSu after the amidation reaction, being especially suitable for the amidation of Fmoc-protected amino acids.