Aspects of tautomerism. Part 16. Influence of the y-keto function on the reactions of sulphonic acids

Reaction of sodium 2-formylbenzenesulphonate (1) with thionyl chloride or phosphorous pentachloride gives a mixture of pseudo (2) and normal (3) sulphonyl chlorides. Whereas ammonium 2-carboxybenzenesulphonate (6) gives only the normal sulphonyl chloride (7) on reaction with thionyl chloride, a mixture of normal (7) and pseudo (8) isomers are formed on reaction with phosphorous pentachloride. Sodium 2-benzoylbenzenesulphonate (15), on the other hand, gives the corresponding normal sulphonyl chloride (16) on reaction with both of the reagents mentioned above. Based on these observations it is concluded that γ-keto sulphonic acids are amenable to the influence of γ-carbonyl group as in the case of γ-keto carboxylic acids but to a lesser extent.     

Current status and prospects of development of the NAAPRO code

The paper contains a summary of the recent developments of the prediction part of the NAAPRO (Neutron Activation Analysis PRognosis and Optimization) code. Specific details are given for the activation product yield calculation approach used in the program and for the nuclear data libraries. The prospects for the code development are discussed.     

Raman-spectrum investigation of the conformations of cis-and trans-1,3-dimethylcyclohexanols

Summary When configurations are named with respect to the actually largest substituents, the preferred conformation for the compound (I) in the liquid phase is trans-1e3a, and for compound (II) in the liquid phase cis-1e3e with equatorial hydrogen-bonded hydroxyls; when this nomenclature, based on the actually largest substituents is used, the Auwers-Sktta rule is not reversed for the compounds (I) and (II) in the liquid state.     

Raman-spectrum investigation of the equatorial and axial carbonyl groups of some substituted cyclohexanes

Summary In the determination of conformations in accordance with the largest substituents it is found that compound (IV) has the conformations trans-ee and trans-aa and compound (V) the conformations cis-ae and cis-ea; none of these conformations predominates substantially, as with neither of the two possible conformations of the compound (III).     

A study of the process of lignification of one-year willow wood

Conclusions 1. The content of lignin in the wood ofSalix viminalis andSalix acutifolia increases with the growth of the shoots during shortened days and also in drier climatic periods.2. The monosaccharides, glucose, fructose, and arabinose take part in the synthesis of the lignin of young wood ofSalix viminalis andSalix acutifolia. The formation of lignin of one-year willow wood takes place from May to January (with a maximum in June–July). The content of methoxyl groups in it gradually rises.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 6, pp. 546–550, 1969     

Phospholipids of the seeds of two species of Erysimum

Summary The phospholipid complexes of the seeds ofErysimum diffusum andE. sylvestris have been investigated. It has been found that the amount of phospholipids in the seeds ofE. diffusum is lower than in those ofE. sylvestris, but their qualitative compositions are similar. The fatty-acid compositions of the triglycerides and of the total phospholipids of the two plants investigated have been studied. It has been established that the total phospholipids of the species ofErysimum under consideration and individual fractions of them differ by the degree of saturation and the qualitative and quantitative composition of the acids that they contain and, consequently, the phospholipids present in greatest amount differ in their molecular compositions.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 623–627, September–October, 1977.     

Oils of the seeds of Ziziphora pedicellata and Eremostachys molluceloides

Summary The fatty oils of the seeds of the wild speciesZiziphora pedicellata andEremostachys molluceloides (Labiatae) have been investigated. The glyceride, pigment, and hydrocarbon compositions of these oils and the fatty-acid composition of the oil ofZ. pedicellata have been determined.The oil ofE. molluceloides contains laballenic acid.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 324–328, May–June, 1975.     

Terpenoids of the oleoresin of Pinus pumila

Summary 1. The composition of the acid fraction of the oleresin ofPinus pumila (Pall.) Regel. has been studied, and from it has been isolated, in addition to known compounds, the methyl ester of a new labdane acetoxy acid.2. In the hydrocarbon fraction of the oleoresin 11 monoterpenes and 26 sesquiterpenes have been found (and 17 of the latter have been identified).3. The composition of the fraction of neutral oxygen-containing diterpenoids fromP. pumila differs considerably in its diterpenoid components from the corresponding fractions of the oleoresins of botanically related species-P. sibirica andP. koraiensis. Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 299–302, May–June, 1976.     

Use of the paramagnetic shift agent Eu(DPM)3 for studying the structure and stereochemistry of conferol and conferone

Summary A spectrophotometric method is proposed for determining the content of aspidin in a crystalline powder and in the rhizomes of the fernsDryopteris spinulosa (M),D. phegopteris (L.), andD. fragrans (L.) Schott.All-Union Scientific-Research Institute for Medicinal Plants. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 684–687, November–December, 1970.     

Synthesis of the Oligosaccharide Moieties of Musettamycin,Marcellomycin and Aclacinomycin A,Antitumor Antibiotics

Abstract

Condensation of benzyl 2,3,6-trideoxy-3-trifluoroacetamido-α-L-lyxo-hexopyranoside (5) with 4-O-acetyl-3-O-benzyl-2,6-dideoxy-α-L-lyxo-hexopyranosyl bromide (10) carried out under Koenigs-Knorr conditions gave 12. Total deprotection of 12 and N-dimethylation at C-3 led to 17 while selective removal of the 4-O-acetyl group led to 13, a synthetic intermediate for preparing 24 and 33. Condensation of 13 with di-O-acetyl-L-fucal (18) or 4-O-acetyl-L-amicetal (25) in the presence of N-iodosuccinimide followed by hydrogenolysis of the C-2-I bond gave 20 and 27 respectively. The trisaccharide 24 then was obtained from 20 by the same sequence of reactions used to convert 12 into 17. After deacetylation and oxidation, this set of reactions also transformed 27 into 33.     

Oils of three representatives of the family Cruciferae. II

Summary The physicochemical properties and fatty-acid composition of the oils of the seeds ofLepidium sativum, Eruca sativa, andThlaspi arvense, with oil contents of 23.08%, 33.46%, and 29.18%, respectively, have been determined. The amounts of erucic acid, which is characteristic for Cruciferae, found were 4.71% in the oil ofL. sativum, 37.18% in that ofE. sativa, and 23.04% in that ofTh. arvense.For communication I, see [1].Zaporozh'e Medical Institute. Ukrainian Scientific-Research Institute of the Oils and Fats Industry. Basic Scientific-Research Laboratory, Ukrainian Scientific-Research Institute of the Oils and Fats Industry at the Zaporozh'e Oils and Fats Combine. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 440–442, July–August, 1974.     

Preparing aromatic selenium compounds through the aryl diazonium borofluorides

Summary By decomposition of aryl diazonium borofluorides with powdered zinc in the presence of selenium terrachloride in acetone we have obtained diaryl selenides with aryls: phenyl,p- ando-tolyl,p-chlorophenyl, andp-methoxyphenyl.     

Two new xenicin diterpenoids from the octocoral anthelia edmondsoni

From the soft coral Antheliaedmondsoni two new diterpenoids, waixenicin-A (1) and -B (2) have been Isolated. Their structures were elucidated by¹H and¹³C NMR analysis and the relative stereochemistry was determined by x-ray diffraction of crystalline waixenicin-B (2).     

The chemical composition of the wood of some species of willow

Summary 1. The following monosaccharides have been found in the carbohydrate composition of readily hydrolyzable poly-saccharides of one-year willow wood: xylose, glucose, arabinose, galactose, and mannose, with xylose predominating.2. The unhydrolyzable residues obtained from the hydrolysis of unbarked willow wood contain a large amount of carboxyl groups, from 0.62 to 1.00 meq/g.3. The most promising willow species for use in the chemical wood-processing industry are those containing a large amount of polysaccharides including cellulose and the smallest amount of nonhydrolyzable residue:S. vitelina 66.46% of polysaccharides and 18.76% of nonhydrolyzable residue,S. urabensis 61.96 and 20.85%, respectively,S. superba 59.52 and 20.50%,S. viminalis gigantea 59.20 and 21.40%, andS. purpurea 58.44 and 23.30%.Khimiya Prirodnykh Soedinenii, Vol. 3, No. 6, pp. 392–395, 1967     

The effect of sulfur and selenium substitutents on the regiochemistry of diels-alder reactions

2-Phenylthio-1,3-butadiene (1) and 2-phenylseleno-1,3-butadiene (2) have been generated in situ from their SO₂ adducts and reacted with a series of unsymmetrical dienophiles. The regiochemical results have been analyzed in terms of qualitative perturbation theory.     

Synthesis and structure of hexakis (p-hydroxyphenyloxy)benzene: A versatile analogue of the hydrogen-bonded hexameric unit of β-hydroquinone

The title hexaphenol (1), a direct analogue of the -hydroquinone hexameric unit, has been prepared by six-fold demethylation of hexakis (p-methoxyphenyloxy)benzene (2) with BBr₃. Host1 forms a trigonal adduct, space groupR3,a=22.088(3),c=12.232(3) Å, containing 6 molecules of pyridine per host molecule: a detailed X-ray study of this inclusion compound reveals a true clathrate structure, the closed cages of which accommodate a small, non-stoichiometric amount of water.     

Synthesis of Glycosyl Cyanides and C-Allyl Glycosides by the use of Glycosyl Fluoride Derivatives

A treatment of 2,3,5-tri-O-benzyl-B-D-ribofuranosyl fluoride (1) with cyanotrimethylsilane in the presence of boron trifluoride diethyl etherate gave 2,3,5-tri-O-benzyl-α- (2α) and -β-D-ribofuranosyl (2β) cyanide in 46.2% and 46.6% yields, respectively. Confirmation of the corresponding isocyano isomer (3) formation and its conversion into 2 under boron trifluoride catalysis at -78°C made it possible to deduce that both 2α and 2β were produced by way of 3 which was formed preponderantly in the initial stage of the reaction. On the other hand, the reaction of 2,3,4,6-tetra-O-benzyl-α-D-glucopyranosyl fluoride (4) with cyanotrimethylsilane in diethyl ether by the use of boron trifluoride diethyl etherate (0.05 mol. equiv.) gave 2,3,4,6-tetra-O-benzyl-α -D-glucopyranosyl cyanide (5α), 2,3,4,6-tetra-O-benzyl-α- (6α), and -β-D-glucopyranosyl isocyanide (6β) as a 30:61:9 mixture (94% yield) but that in dichloromethane by the use of the catalyst (1.0 mol. equiv.) gave 5α (85% yield) as a sole product.

The reactions of 1 and of 4 with allyltrirnethylsilane under the same catalysis afforded C-allyl 2,3,5-tri-O-benzyl-α-D-ribofuranoside (7)(93.5% yield), and C-allyl 2,3,4,6-tetra-O-benzyl-α- (8α)(71.8% yield) and -β-D-glucopyranoside (8β) (22.4% yield), respectively.     

Study on the method of chemical trapping for formyl intermediates

The method of chemical trapping for formyl intermediates has been studied, with syngas conversion to ethanol over rhodium-based catalysts as the diagnostic reaction concerned, and CH₃I as the trapping reagent. Two species of acetaldehyde, i.e., CH₃CHO and CH₃CDO, were produced in the trapping reaction following CO + 2D₂ reaction. It was shown that the formation of CH₃CHO in the trapping reaction resulted from dehydrogenation of CH₃ from CH₃I to give H, which induced the formation of CH₃CHO in the presence of CO and CH₃ So there may be two pathways for the formation of CH₃CDO in the trapping reaction: one, methylation of DCO adspecies; the other, deuteration of CH₃ CO formed by CO insertion into CH₃ The catalyst surface was purged with Ar following CO + 2D₂ reaction before the trapping reaction was performed. By means of this modified method of chemical trapping for formyl intermediates, CH₃CDO was found to be mainly derived from the methylation of DCO adspecies. Accordingly, it could be concluded that formyl is a C₁ intermediate in the syngas conversion to ethanol over rhodium-based catalysts.     

Determination of the positions of the sulfate groups in sulfated polysaccharides

1. The possibility has been shown of using a method proposed by us previously to determine the positions of the sulfate groups in sulfated polysaccharides. 2. The positions of the sulfate groups in the following sulfated polysaccharides have been determined: fucan and pelvecyan fromPelvetia wrightii and sargassan fromSargassum pallidum.     

On the Mechanism and Scope of a Novel Nitroolefin Rearrangement

D-Labelling permits differentiation between three plausible mechanistic pathways in the novel transformation of vinylaziridine 1 with β-nitrostyrene 4 to nitro enamino olefin 5. The results are consistent with a retro-ene reaction proceeding under mild conditions (80°). Choice of proper substituents can guide the reaction toward formation of azepines or substituted enamines.