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The association between lignin and carbohydrates in the lignified plant cell walls is of fundamental importance for characterizing the structure and function of cell walls, improving the pulping and bleaching processes and utilizing lignocellulosic plants as biomass.

The reactions of the benzyl ether (1b) of kojic acid (la) and its chloromethyl derivative (1c) were investigated as new routes to fused heterocyclic systems. The chloromethyl compound proved the more versatile intermediate yielding benzothiazoles with thiourea and pyrido[l,2-a]benzimidazoles (11) and pyrido[1,2-alindole (12b) with pyridine derivatives. A number of methylated products of the benzothiazole were prepared in order to establish the structures of the reaction products and a possible mechanism of the reaction is discussed.

The science of biodegradable materials is most often associated with problems of environmental control. The need to avoid accumulation of permanent ecological litter is obvious and methods to do so will not be considered in this discussion. Rather, the emphasis will be on polymers with the potential for degradation within the living organism. More specifically, polymers which display structural integrity and, as a consequence, mechanical utility, will be considered while polymeric drugs or carriers which function in solution, such as polyvinyl pyrollidone and dex-tran, both reported as useful blood extenders, will not.

The psychotomimetic activity of the variety of hemp known as Cannabis sativa has been known since antiquity. Various preparations of this plant under the names of marijuana, hashish, charas, dagga, and bhang are smoked or chewed by possibly two to three hundred million people. Accordingly, these materials undoubtedly constitute the most widely used group of illicit drugs. The chemistry of these Cannabis constituents studied extensively during the 1940’s by Todd and his colleagues and the late Roger Adams and his students has been reviewed1-2-3-4. However, real progress in the isolation, structural elucidation and synthesis of the various cannabinoids has come only in the last decade, aided by the numerous modern separation methods, analytical techniques, and, most notably, by the development of NMR and mass spectrometry.

The increasing number of reports, monographs and patents dealing with the hemistry of inclusion compounds shows the growing interest of organic chemists in elaborating new chemical systems presenting novel physical and chemical properties. These properties are available for fundamental as well as applied research. On the one hand, basic studies on the structure and the nature of inclusion compounds provide information on the intermolecular forces implicated in organized systems and in enzyme processes. On the other hand, applications are in progress in laboratories and industries, for instance, in catalyzing chemical reactions, in transporting and extracting metallic cations, and in modifying the chemical properties of drugs and dyes. Applications in physics in the near future have been envisaged in the design of components able to treat information and signals at the molecular level [1].

2,3-Dihydroheliparvifoline (Va) was obtained from 4-methoxy-3-benzyloxyaniline by condensation with diethyl (2-benzyloxyethyl)-malonate, and by subsequent methylation, debenzylation, and then cyclodehydration. Benzyl ether of Va was dehydrogenated and then treated with hydrochloric acid to give heliparvifoline.

A large glove-box facility for handling reactive metal tritides was decommissioned. Major sections of the glove box were decontaminated and disassembled for reuse at another tritium facility. To achieve the desired results, decontamination required repeated washing, first with organic liquids, then with water and detergents. Worker protection was provided by simple ventilation, which was combined with careful monitoring of the work areas and employees. Several innovative techniques are described.

Thin-layer chromatography affords a simple, rapid and sensitive method for the qualitative and quantitative analysis of low molecular weight sugars and their derivatives. In the few years since Stahl and Kaltenbach [1] extended TLC to the separation of sugar mixtures, the method has been adopted for a wide spectrum of analytical problems. This chapter considers two classes of compounds: the hydrophilic carbohydrates and their derivatives which are hydrophobic in nature.

From the Flory-Stockmayer theory and molecular weights of successive fractions of lignin obtained by extraction of spruce wood with a mixture of water, dioxane, and hydrochloric acid and by sulfonation, the average length of the primary chains was estimated to be 18 phenylpropane units. From data on the acid-catalyzed cleavage of model compounds in various solvents the degrees of cross-linking in four extraction processes were calculated. The average degree of cross-linking of intact lignin was found to be 0.277; that is, 5 out of every 18 phenylpropane units bear cross-linking benzyl ether groups. Of the five, three are also etherified at their phenolic ends (B groups), and two are not (X groups).

The lower representatives of the aliphatic mercaptan series (up to C4) are effective fumigants against some species of insects. Beginning with the C5 alkyl mercaptan the insecticidal properties decrease. The unsaturated mercaptans are somewhat more active than the saturated ones with the same number of carbon atoms.

Alcohols react with alkylating and acylating agents; they also react with other electrophiles: e.g., primary and secondary alcohols may be oxidized, and tertiary alcohols are especially susceptible to acid-catalyzed dehydration. It is therefore often necessary to protect alcoholic hydroxyl groups if it is intended to effect a chemical reaction solely at another site in a molecule. Such protection also prevents the possibility of neighbouring group participation by hydroxyl groups.

A gas chromatographic fraction of a sample of basil oil was found to contain benzyl ether, a compound heretofore not reported to be present in this oil. Identification was established by comparison of various spectra of known samples of the ether. It was further observed that the published mass spectral data for benzyl ether was in error.

The Vogel's reaction cascade (one-pot hetero-Diels-Alder addition of SO 2 , ionization of the sultines into zwitterions and their quenching by electron-rich alkenes) has been applied to the preparation of enantiomerically-enriched (1S)-2((2R)-l-benzoylpyrrolidin-2-yl)pentan-3-one (14). Reaction of SO 2 with (-)-(1E',3Z)-2-methyl-1-((1S')-1-phenylethoxy)penta-1,3-dien-3 -ol benzoate (5: derived from (S)-1-phenylethanol (97% ee)) and allyltrimethylsilane in the presence of a Lewis acid at -78°C provides (-)-(2Z,1'S,45,55)-4-methyl-5-(l'-phenylethoxy)octa-2,7-dien-3-ol benzoate (9). Selective cleavage of the benzyl ether of 9 and subsequent S N 2 displacement with Ph 2 P(O)N 3 provided an azide 11 that was converted into 14.

Synthesis of second generation poly(benzyl ether) dendrimers having N3O porphyrin at its core and the first observation of large micro-meter sized spherical aggregates as confirmed by optical microscopy and AFM analysis are reported.

A new synthesis of α-santalol (1) is described. 1-Benzyloxy-4-bromo-2-methyl-2-butene (6) was converted by the reaction with nickel carbonyl to the π-allylic nickel bromide complex (7), which reacted with (−)-π-bromotricyclene (8) to afford benzyl ether (2). The benzyl ether (2) was led to (1) (cis: trans=40: 60) by reductive cleavage of the benzyloxy group.

The reaction of tetrasulfur tetranitride with alkoxybenzenes such as anisole (1a), o- (1b), m-(1c), p-dimethoxybenzenes (1d), and benzyl ether (1e) was investigated. Benzo[1,2-c:3,4-c′ :5,6-c ]-tris[1,2,5]thiadiazole (2) and benzo[1,2, c:3,4-c′ ]bis[1,2,5]thiadiazoles (3a and 3b) were isolated. J. Chem. Soc., 14, 963 (1977)

The generation of an electrophilic centre on the 11β-(2-hydroxyethyl) estradiol 3,17β-bis(benzyl ether)(2) leads in two steps to the corresponding 1,11β-ethano-estradiol in a 61% overall yield.

A kinetic study has been performed for the reaction of (aryloxy)trimethylstannane with benzyl bromide giving aryl benzyl ether and bromotrimethylstannane. Bimolecular nucleophilic attack of the ary...

2,3-Dihydroheliparvifoline (Va) was obtained from 4-methoxy-3-benzyloxyaniline by condensation with diethyl (2-benzyloxyethyl)-malonate, and by subsequent methylation, debenzylation, and then cyclodehydration. Benzyl ether of Va was dehydrogenated and then treated with hydrochloric acid to give heliparvifoline.

SUMMARY Analysis of a commercial sample purported to be cold-pressed lemon oil, USP, revealed anomalies in both the ultraviolet spectrum and the gas chromatogram. A chemical not natural to lemon was isolated by preparative gas-liquid chromatography and shown to be benzyl ether by nuclear magnetic resonance and infrared spectroscopy.

Polyphosphoric acid has been found to isomerize cis-p-methoxycinnamic acid to trans-p-methoxycinnamic acid and to cleave a benzyl ether; however, there is no evidence for the previously reported trans- to cis-isomerization of cinnamic acids.

The reaction of chlorodiphenylphosphine (1a) with benzaldehyde in the presence of acetic acid has been re-examined. The final products have been isolated and identified as α-acetoxybenzyldiphenylphosphine oxide (4) and bis-α-(diphenylphosphinoyl)benzyl ether (5). The relative amounts of (4) and (5) formed are markedly influenced by the proportion of aldehyde in the reaction mixture.

Removal of urethane and benzyl ether blocking groups from peptides is readily accomplished by treatment with trimethylsilyl iodide which is particularly useful for the debenzylation of O-benzyltyrosine without the formation of rearrangement products.

An ortho-effect has been found for the loss of Cl· from the molecular ions of chlorodiphenyl ethers, sulphides, and sulphoxides. This was not observed for the corresponding sulphones and o-chlorophenyl benzyl ether, owing to the competition of other, energetically more favourable, reactions. The reaction due to the ortho-effect in the molecular ions of o-chlorodiphenyl ether, sulphide, and sulphoxide were the lowest-energy processes, competing successfully with rearrangements. In the case of the three chlorodiphenyl sulphides, there was indication for a different structure of the ortho-(M– Cl)⌉+ ion from those of the meta- and para-isomers. Chlorine scrambling in simple disubstituted benzenes is discussed in view of the results.