4-Hydroxy-5-hydroxyimino-7-methyl-5H-pyrano (2,3-b) pyridine 8-oxide (author's transl)

4-Hydroxy-5-hydroxyimino-7-methyl-5H-pyrano[2,3-b]pyridine 8-Oxide In the course of studies on the reaction between dehydroacetic acid ( 1 ), N,N-dimethylformamide dimethyl acetal and hydroxylamine, a new two-step synthesis of a pyranopyridine with the structure of a vinylogous hydroxamic acid was discovered. The isomeric structures 5a - 8b , derived from the empirical formula C₉H₈N₂O₄ are discussed. The existence of 5a in solution is indicated by the spectral data (ms, ir, nmr).     

Nitrones of 5-(alpha-hydroxylaminoalkyl)-tetrazoles (author's transl)

Nitrones of 5-(α-Hydroxylaminoalkyl)-tetrazoles The title-compounds were obtained by dehydration with yellow mercuric oxide, and some of them were converted to derivatives of 1,2,4-oxadiazolidin-5-one with aryl isocyanates via 1,3-dipolar cycloaddition.     

Nitration of methylphenobarbitone and 5-ethyl-5-phenylhydantoin (author's transl)

Nitration of Methylphenobarbitone and 5-Ethyl-5-phenylhydantoin Ethylphenylhydantoin ( 1a ) and methylphenobarbitone ( 2a ) were nitrated by KNO₃/ concentrated H₂SO₄. Four nitro derivatives from 1a and six from 2a were isolated by preparative TLC and crystallization. Their structures were elucidated by i. r. and n.m.r. spectroscopy. In each case nitro substitution took place at the aromatic ring. On nitration, 2a is partially N-demethylated.     

Dialkylaminoethoximino-propanes (author's transl)

Dialkylaminoethoximino-propanes β-Dialkylaminoethoximines 1 may be obtained from β-dialkylaminoethoxyamines 2 . which are synthesized from substituted acetone oximes 3 . The ¹HNMR-spectra of 3 show different chemical shifts of the methyl groups. These coalesce at higher temperatures. The temperatures of coalescence are measured, and the enthalpies of activation are calculated according to Eyring.     

Derivatives of 3- and 5-aminosalicylamides (author's transl)

Derivatives of 3- and 5-Aminosalicylamides Three kinds of the compounds mentioned in the title were synthesized via the corresponding nitro compounds: 3- and 5-aminosalicylamides of various secondary amines, their O-acetyl derivatives and the corresponding basically substituted ethers.     

Synthesis and properties of 5-deazaflavinium salts (author's transl)

Synthesis and Properties of 5-Deazaflavinium Salts The 1,3,10-Trimethyl-5-deazaflavinium salt 5 , which cannot be prepared by methylation of 5-deazaflavins, is formed by acidic cleavage of 15 , which in turn is formed by condensation of N-methylanthranilaldehyde ( 11 ) with dimethylbarbituric acid (12 ). The stability of 5 in aqueous solvents and its reduction to 6 are studied. The reactivity of position 5 in deazaflavinium cations is discussed with respect to their similarity with NAD.     

Vestibular pharmacology (author's transl)

The paper deals with recent advances in anatomical, physiological, biochemical and pharmacological studies on the vestibular system. Fiber connections and characteristics of neurons in the vestibular nuclei were discussed in relation to regulation from other structures such as the cerebellum, oculomotor nuclei, reticular formation and spinal cord. In addition, a review was made of the actions on the vestibular system of antivertigo drugs including anticholinergic and antihistamine drugs, tranquilizers and barbiturates. All the obtained data show that the vestibular nuclei are devoid of noradrenergic, dopaminergic and serotonergic innervation, in contrast to other brainstem nuclei. Acetylcholine is apparently a neurotransmitter in the afferent transmission from the vestibular nerve to the vestibular nuclei. Antivertigo drugs produce modification in the neuron activity in the medial and lateral vestibular nuclei.     

Vinylogue hydrazidines (author's transl)

Vinylogue Hydrazidines Reaction of 3,4,5-trichloro-6-dimethylamino-fulvene-2-aldehyde (2) with unsymmetrically substituted hydrazines yields the vinylogue hydrazidines 8a–e with an intramolecular hydrogen bond.     

1-Isocyanato-homoisochromanes (author's transl)

1-Isocyanato-homoisochromanes 1-Isocyanato-homoisochromanes 2 are obtained from 1-bromohomoisochromanes 1 with silver cyanate in dry ether. Upon hydrolysis of 2 the N,N′-bis[homoisochromanyl-1]-ureides 4 are formed. With ammonia or primary amines 1-isocyanato-homoisochromanes 2 yield the homoisochroman-1-yl ureides 3 ; reactions with alcohols give the homoisochroman-1-yl carbamates 5 .     

Quinolylidene derivatives (author's transl)

Quinolylidene Derivatives The 4- and 2-quinolones 1a–h, 2, 19a and 11, 12 react with CH-acidic compounds to yield the quinolylidene derivatives 7a–i, 8a, 8b, 9a–d, 10a, 10b, 22 and 13a, 13b, 14 , respectively. The formation of salts by some quinolylidenes with acids and bases is investigated.     

C-Mannich bases of 5-hydroxybenzimidazole (author's transl)]

C-Mannich Bases of 5-Hydroxybenzimidazole . 5-Hydroxybenzimidazole ( 3 ) reacts with aliphatic and cyclic secondary amines to give remarkably stable 4-aminomethyl-5-hydroxy-benzimidazoles 4 with a yield of 20 to 60%. Intermediates in the formation of the new bases are carbenium-immonium-ions.     

Studies of D-penicillamine (5): effects on rat adjuvant arthritis (author's transl)

D-Penicillamine (D-PA), 80-100 mg/kg/day enhanced the early phase of adjuvant arthritis (AA) in rats when it was administered orally for about 4 weeks after the adjuvant injection day, whereas dexamethasone (1 mg/kg/day, p.o.) and chloroquine diphosphate (25 mg/kg/day, p.o.) inhibited AA in the same dosing regimen. On the other hand, subcutaneous injection of sodium aurothiomalate (12.5 mg/kg/day) enhanced AA initially, but inhibited it later. The enhancing effect of D-PA on the early phase of AA was observed also at doses of 50 mg/kg/day and 200 mg/kg/day, but, in the case of 200 mg/kg/day, inhibited the later phase of AA. When the administration of D-PA was started before the adjuvant injection, it showed a tendency to suppress AA on proportion to the dosing period. The effect of D-PA, however, was not observed in the model when the drug administration was started after the establishment of arthritis. The co-administration pyridoxine HCl did not influence the effect of D-PA on AA. A good correlation was not obtained between the inflammatory score and the PPD induced skin reaction, serum metals level and histopathological changes of lymph node in the AA rats treated with D-PA. Thus the effect of D-PA on AA was related to dose, timing and duration of the administration. It was suggested that the enhancing and inhibitory effects of D-PA on AA were not based on vitamin B6, depletion, but rather were caused by inhibition of T1 and T2 lymphocytes which may be regulating this arthritis process.     

Constituents of Essential Oils from Mentha longifolia Growing Wild in Greece

The essential oils from 9 populations of MENTHA LONGIFOLIA (L.) L., ssp. LONGIFOLIA and ssp. PETIOLATA (Boiss.) Kokkini, growing wild in Greece, were investigated by means of GLC and GLC-MS. Piperitone oxide has been found as the main component in the essential oils of both subspecies while carvone only in some individuals of ssp. PETIOLATA (chemotype 2).