From the root of Thalictrum Thunbergii DC. (Japanese name “Akikaramatsu”) growing in Tokushima, a new tertiary phenolic base, thalicrine, was isolated as colorless needles, m.p. 221-222°, [α]D+341.2° (CHCl3), and a new non-phenolic base, homothalicrine, as colorless cubic crystals, m.p. 235-236° (decomp.), [α]D+425.3° (CHCl3). O-Methylthalicrine, obtained by brief methylation of thalicrine with diazomethane, was found to be identical with homothalicrine, from its elemental analytical values, melting point, and infrared spectrum (in chloroform). Composition and empirical formula of thalicrine agree with C36H38O6N2=C32H25O3-(OH)(OCH3)2(NCH3)2 and those of homothalicrine with C37H40O6N2=C32H25O3(OCH3)3-(NCH3)2. The Hofmann degradation of thalicrine dimethochloride and oxidation of its methylmethine with potassium permanganate afforded 4-methoxy-3, 4′-oxydibenzoic acid (I). The same Hofmann degradation of O-ethylthalicrine and permanganate oxidation of its methylmethine afforded an acid of m.p. 274-275°. In order to elucidate the structure of this acid, O-ethylberbamine (II) was submitted to the same degradation and oxidation, and authentic sample of 4-ethoxy-3, 4′-oxydibenzoic acid (V) thereby obtained was found to be identical with the foregoing acid of m.p. 274-275° in melting point and infrared spectrum (in Nujol). From these experimental evidences and ultraviolet spectra (Fig. 1, A-D), the two bases here obtained were considered to be new bases of the biscoclaurine type. It was also proved that the phenolic hydroxyl in thalicrine is in the position ortho to the ether bond connecting the two phenyl rings and para to the benzyl group.
The presence of one cryptophenolic hydroxyl in each of the new bases, thalicrine and homothalicrine, was proved by the following facts. Homothalicrine and its methylmethine are both insoluble in alkali hydroxide or Claisen solution but are positive to the Millon and ammonium phosphomolybdate reactions. Both have a sharp absorption at 3580cm-1 in their infrared spectra. Methylation of thalicrine and homothalicrine with excess diazomethane for two weeks gave identical O-methyl ether (O, O-dimethylthalicrine or O-methylhomothalicrine), in which two and one methoxyl group had been formed respectively in thalicrine and homothalicrine. Methylation only for a few days was found to give homothalicrine from the former and recovery of the starting material from the latter. Cleavage reaction of O-methylhomothalicrine (I) with metallic sodium in liquid ammonia was found to result in almost quantitative fission into two components, d-armepavine (II) and l-1-(4-methoxybenzyl)-2-methyl-6-hydroxy-7-methoxy-1, 2, 3, 4-tetrahydroisoquinoline (III). From earlier experiments, the phenolic hydroxyl in the benzyl group of (II) should have been formed by severance of the ether-oxygen connecting the phenyl group with benzyl group and the phenolic hydroxyl in 6-position of (III) should have been formed by severance of ether-oxygen connecting the two phenyl groups. The other end of the ether bond in (III) was considered to be in 8-position of the isoquinoline ring, from analogy with biogenesis of this type of natural bases. Consequently, the chemical structure of thalicrine and homothalicrine would be a new base formed by substitution of one of the three methoxyls on the isoquinoline side in (VIII: R=H) and (VIII: R=CH3) with cryptophenolic hydroxyl.
In order to prove the position of cryptophenolic hydroxyl present in the new bases, thalicrine and homothalicrine, cleavage reaction of O, O-diethylthalicrine (VI) with metallic sodium in liquid ammonia was carried out. It was thereby confirmed that the base is severed almost quantitatively into two parts, d-1-(4-hydroxybenzyl)-2-methyl-6-methoxy-7-ethoxy-1, 2, 3, 4-tetrahydroisoquinoline (VII) and l-1-(4-ethoxybenzyl)-2-methyl-6-hydroxy-7-methoxy-1, 2, 3, 4-tetrahydroisoquinoline (IX). It follows, therefore, that the cryptophenolic hydroxylin thalicrine and homothalicrine is present in 7-position of the benzylisoquinoline ring on the left side of the formulae (XXI) and (XXII), which are proposed as the chemical structures of thalicrine and homothalicrine, by the summation of experimental evidences obtained to date. It goes without saying that the steric configuration (direction of optical rotation) of the two asymmetric centers in the two bases is (+, -) in both.
(-)-Deoxynupharidine (I) was derived to the alcohol compound (IV) through α-amino acid compound (II) whose specific rotation was measured in neutral, acid, and alkaline aqueous solution. Infrared absorption spectrum of (IV) was measured in carbon tetrachloride solution of various concentrations. Judging from these results, the formula (I′) was proposed for the structure of (I).
Following earlier reports on the reaction of p-aminosalicylic acid (PAS) and of its sodium salt (PAS-Na) in aqueous solution, decomposition of these and other salts was examined by mixing various buffer salts with PAS, PAS-Na, complex salt of calcium p-aminosalicylate (PAS-Ca2), and calcium p-aminosalicylate (PAS-Ca), and maintaining these in a dessicator over saturated potassium nitrate solution or saturated ammonium chloride solution. The buffer salts used were ammonium dihydrogenphosphate, potassium dihydrogenphosphate, sodium oxalate, and borax. Results of these experiments were considered from the point of induction period (t′) and firstorder reaction period. On addition of ammonium dihydrogenphosphate, PAS was the most stable and, since the acid was generally more stable in lower humidity, it was considered that water took part in this reaction. With the addition of potassium dihydrogenphosphate, the induction period of PAS salts was much shorter than that in the use of the ammonium salt, there being almost no induction period at 50° and 60°. However, there was a definite induction period in the case of PAS at all temperatures tested. With the addition of sodium oxalate, both PAS-Ca and PAS-Ca2 showed two induction periods, t1′ and t2′, at 50°, and they were found to be far more labile than other PAS salts at 60°. On the other hand, addition of borax showed the first-order reaction constant, k, to be larger only in PAS-Na, the other three samples showing almost the same values.
Colorimetric determination of chloramphenicol in solution was carried out. To 1cc. of a sample containing chloramphenicol placed in a glass-stoppered test tube, 1cc. of Clark-Lubs buffer of pH 7 and 3cc. of isoamyl acetate are added, the mixture is shaken for 10 minutes, and centrifuged. To 2cc. of this supernatant, 3% isonicotinic acid hydrazide solution and 1cc. of 6% sodium hydroxide solution are added and the mixture is shaken at 30° for 30 minutes. The supernatant layer is removed and absorbancy of the lower colored layer is measured, using S-40 filter. A blank test is carried out at the same time in the same manner, using the same reagents but distilled water in place of the sample solution. Potency of the test solution is calculated from the calibration curve prepared with chloramphenicol of the known potency. This method was tested on samples left at room temperature or in a refrigerater, left as acid or alkaline solution, or boiled. The values so obtained were compared with those determined by the cup method and the values were found to agree well.
Blood level of chloramphenicol in rabbits was measured after oral administration of chloramphenicol crystals or chloramphenicol ester preparation. Estimation of the blood level was made in a following manner. After administration of chloramphenicol, 0.5cc. of blood is drawn, mixed with 0.1cc. of 3.8% sodium citrate, placed in a glass-stoppered test tube, and shaken with 0.2cc. of 1% saponin solution to effect complete hemolysis. To this mixture, 2cc. of the Clark-Lubs buffer (pH 7) and 3cc. of isoamyl acetate are added and the mixture is shaken for 10 minutes to effect extraction. This is centrifuged, 2cc. of the supernatant is mixed with 1cc. each of 3% isonicotinic acid hydrazide solution and 6% sodium hydroxide solution, and shaken in a thermostat of 30° for 30 minutes. The supernatant is decanted and absorbancy of the colored underlayer is measured (filter, S-40; light path, 5mm.). The blood drawn before administration of chloramphenicol is treated in the same manner and its absorbance is measured as the control. Blood level of chloramphenicol is calculated from the calibration curve.
In vivo change of chloramphenicol was examined by measuring urinary excretion of chloramphenicol. One cc. of urine obtained after administration of chloramphenicol was placed in a glass-stoppered test tube, 1cc. of the Clark-Lubs buffer (pH 7) and 3cc. of isoamyl acetate were added, and shaken for 10 minutes. The mixture was centrifuged, 2cc. of the supernatant was mixed with 1cc. each of 3% isonicotinic acid hydrazide solution and 6% sodium hydroxide solution, and shaken in a thermostat of 30° for 30 minutes. This supernatant was decanted and absorbance of the colored underlayer was measured (filter, S-40; light path, 5mm.). The urine obtained before administration of chloramphenicol was treated in the same manner to be used as the control and urinary concentration of chloramphenicol was obtained from the calibration curve. At the same time, total amount of nitro compound excreted was measured by the diazotization method and the amount of chloramphenicol changed in the body was obtained from the difference in the value of these amounts.
Absorption of chloramphenicol from the stomach and small intestine of a rat was examined with solutions of various pH and the effect of metal salts on this absorption was examined. For absorption through the stomach, a definite quantity of chloramphenicol solution was injected into the rat stomach, the liquid was taken out after 1hour, and absorption rate was calculated from the decrease in its weight. For absorption through the intestinal canal, a definite quantity of the sample solution was perfused through the rat small intestine, the sample was taken out after 0.5, 1.0, and 1.5hours, and the amount of chloramphenicol was determined. Absorption rate was calculated from the decrease in weight. It was thereby found that absorption rate through the stomach was around 10% with solutions of various pH but approximately 50% absorption rate was found after 1.5 hours. The absorption rate was also examined with sample solutions added with ferric chloride, calcium chloride, magnesium chloride, or aluminium chloride, and it was found that absorption of chloramphenicol from both the stomach and small intestine was inhibited by the addition of metal salt to the acid solution.
N-(3, 4-Dimethoxyphenethyl) urea, obtained by heating of 3, 4-dimethoxyphenethyl-amine hydrochloride with urea, was cyclized to 1-amino-6, 7-dimethoxy-3, 4-dihydroisoquinolinium chloride (II or II′) with phosphorous pentoxide and phosphoryl chloride. (II) or (II′) gave N-(2-cyano-4, 5-dimethoxyphenethyl) benzenesulfonamide (III) when it was treated with benzenesulfonyl chloride in alkaline solution.
Some experimental pharmacological observations were made on N, N-diethyl-2-(2-methoxy-4-allylphenoxy) acetamide as an anesthetic. Its anesthetic effect lasts only a short time and there are some respiratory stimulative and analeptic effect on the cardiovascular system. There is no cumulative action with average clinical dose and N, N-diethyl-2-(2-methoxy-4-allylphenoxy) acetamide is a true, very short-acting agent. On the other hand, it is hardly soluble in water, produces some irritation on the vein wall, and has a very little analgesic action. Thirty-four kinds of 2, 4-disubstituted phenoxy compounds were prepared to clarify the relationship between chemical structure and anesthetic effect of N, N-diethyl-2-(2-methoxy-4-allylphenoxy) acetamide derivates.
Relationship between structure and activity of N, N-diethyl-2-(2-methoxy-4-allyl-phenoxy) acetamide derivatives was examined by assay of anesthetic action in a rat. 1) Anesthetic effect was lost by the absence of an acid-amide bond in the side chain at 1-position of the benzene ring or by introduction of an ethylene group in the said acid amide side chain. The anesthetic action also decreased on substitution of the acetamide group with propionamide. This derivative in which CH2 and CO in the side chain at 4-position in a reversed order showed only an analgesic action and no anesthetic effect. 2) By substitution of the amino group in this acetamide, respiration excitement was great and anesthetic action slight when the alkyl group was larger than diethyl. With N, N-dimethyl group, the respiration was inhibited and anesthetic effect was markedly short. Other N, N-substituted derivatives were no better than the diethyl compound. 3) Derivatives of 2-(2-methoxy-4-allylphenoxy) acetamide with glycerol ether in the 1-position of the benzene ring showed transitory convulsion, with obscure anesthetic action. 4) Loss of 2-methoxy and/or 4-allyl groups from the benzene ring in 2-(2-methoxy-4-allylphenoxy) acetamide resulted in marked decrease of anesthetic action. Its derivatives with amino group alone or glycerol ether group in 2-position of the benzene ring were entirely without anesthetic action. 5) Transposition of the allyl group from 4- to 6-position in the benzene ring of 2-(2-methoxy-4-allylphenoxy) acetamide resulted in decrease of anesthetic activity. Substitution of allyl group in 4-position with 1-propenyl group did not affect the anethetic activity. Its derivative with carboxyl in 4-position lacked anesthetic activity but its derivation to an ethyl ester produced this effect, though weak. Substitution of the allyl group in 4-position with propyl group produced anesthetic activity about one-half that of the parent compound but the activity was rather long-lasting and recovery was more rapid than that from barbiturates. 6) No changes in anesthetic effect or other pharmacological activity were observed on introduction of a barbituric acid group in 4-position of the benzene ring, its reduction, introduction of barbituric acid or 5-ethylbarbituric acid group in 1-position in 2-(2-methoxy-4-allylphenoxy) acetamide.
Relationship between physicochemical properties and anesthetic activity was examined with 34 kinds of compounds related to N, N-diethyl-2-(2-methoxy-4-allylphenoxy)-acetamide. Minimal anesthetic concentration and saturation concentration of these compounds at 25° against tropical fish, guppy (Lebistes reticulates), were determined, as well as Ferguson's thermodynamic activity. Distribution ratio of these compounds between water and oleyl alcohol was measured by the method of Meyer and Hemmi, and concentration of the compounds in oleyl alcohol at anesthetic concentration was calculated. Thermodynamic activity was calculated from the surface activity of the saturated solution and effective anesthetic solution, according to the method of Feursteine. It was thereby assumed that N, N-diethyl-2-(2-methoxy-4-allylphenoxy)-acetamide and N, N-diethyl-2-(2-methoxy-4-propylphenoxy) acetamide had the same action mechanism as ether and chloroform.
Animal experiments were made on the anesthetic action, accumulation, acute and chronic toxicity, leucocytosis, and metabolism of N, N-diethyl-2-(2-methoxy-4-propylphenoxy) acetamide, usiug its emulsion. It was found to have better points than its 4-allylphenoxy derivative and capable of being used clinically. Examination of metabolites was made with a rabbit and urinary metabolites were presumed to be N, N-diethyl-2-(2-methoxy-4-carboxyphenoxy) acetamide, lacking in anesthetic activity, and a minute quantity of (2-methoxy-4-carboxyphenoxy) acetic acid.
Synthesis of isoquinolines substituted with pyrimidine in 1-position was attempted since no such compounds seem to have been prepared. The starting materials prepared were 2-phenyl- (Ia), 2-o-tolyl- (Ib), and 2-p-tolyl-4-methyl-5-pyrimidinecarbonyl chloride (Ic), 2-p-tolyl-4-methyl-5-pyrimidinecarbonylazide (IIc), and 2-p-tolyl-4-methyl-5-ethoxycarbonylpyrimidine (IIIc). Condensation of (Ia) and homopiperonylamine (IV) afforded the corresponding acid amide (VIa), and condensation of (Ia), (Ib), (Ic), (IIc), and (IIIc) with α-methyl-β-(3, 4-methylenedioxyphenyl) ethylamine (V) also afforded the corresponding acid amides (VIIIa, b, c). These amides (VIa, VIIIa, b, c) were submitted to isoquinoline cyclization by the Bischler-Napieralski reaction and the objective isoquinolines (VIIa, IXa, b, c) were obtained, although in somewhat poor yield.
Isoquinolines substituted in 1-position with 2-oxo-2H-1-benzopyran-3-y1, 2-oxo-6-nitro-2H-1-benzopyran-3-y1, or 2-oxo-2H-1-benzopyran-6-y1 group are unknown in literature and their syntheses was attempted. The chlorides (II, VII, XII) or esters (III, VIII, XIII) were each condensed with α-methyl-β-(3, 4-methylenedioxyphenyl)-β-methoxyethylamine (XVI) to form the corresponding acid amides (XVIIa, b, c) and these were submitted to isoquinoline cyclization by the Bischler-Napieralski reaction. Although the yield was not satisfactory, desired isoquinolines were obtained as free bases of 1-(2-oxo-2H-1-benzopyran-3-y1)-3-methyl-6, 7-methylenedioxyisoquinoline (XVIIIa), 1-(2-oxo-6-nitro-2H-1-benzopyran-3-yl)-3-methyl-6, 7-methylenedioxyisoquinoline (XVIIIb), and 6-(3-methyl-6, 7-methylenedioxy-1-isoquinolyl)-coumarin (XVIIIc).
Syntheses of isoquinolines substituted with furan ring in 1-position or with 5-nitro- or -bromo-furan ring in the 2-position was attempted. 2-Furoyl chlorides (III) substituted with 5-nitro or 5-bromo group, and 2-furoylazide (VIa), 2-(5-nitro) furoylazide (VIb), 2-(5-bromo) furoylazide (VIc) were prepared from furfural, and α-methyl-β-(3, 4-methylenedioxyphenyl)-β-methoxyethylamine (VIII) was prepared from safrol by the usual process. Condensation of this amine (VIII) with the chlorides (III) and azides (VI) afforded the corresponding acid amides (IX). Bischler-Napieralski condensation of these acid amides successfully afforded isoquinolines as free bases; 1-(2-furyl)-(Xa: R=H), 1-(5-nitro-2-furyl)-(Xb: R=NO2), and 1-(5-bromo-2-furyl)-3-methyl-6, 7-methylenedioxyisoquinoline (Xc: R=Br).
In order to examine proteolytic digestibility of acid-stable enzyme during a period corresponding to digestion time in stomach, comparative studies were made on TPR-18 enzyme (Vernase), prepared from Aspergillus oryzae var. microsporus TPR-18, saccharated pepsin (JP), and pancreatin (JP). 1) Optimal pH (pH 3) of TPR-18 enzyme for various proteins (milk casein, soybean casein, hemoglobin, gluten, and egg albumin) was more invariable than those of other enzymes or TPR-18 enzyme (in neutral). 2) Difference in digestibility for various kinds of proteins was found among TPR-18 enzymes (in acid and neutral) and other enzymes at each optimal pH until 5 hours. 3) Curves for digestive ratio from non-protein-N and amino-N were compared with digestive enzymes at each optimal pH until 5 hours and the ability for formation of amino acid by TPR-18 enzyme (pH 6, 3) was higher than that of other enzymes. 4) By the application of molecular sieve of ion-exchange resin, composition of digestion products for protein substrate by TPR-18 enzyme (pH 3) and pepsin was determined by the degree of average peptide length. It was concluded from these experiments on fractionation that TRP-18 enzyme (pH 3) digested protein to small molecules of peptide or to amino acid.
Substitution reaction of 1-position in cyclohepta [b] pyrrol-8 (1H)-one derivatives (Ia-d) was examined and the reaction similar to that in indole compounds was found to be present. Reaction of (I) with acrylonitrile afforded 1-(2-cyanoethyl)-8H-cyclo-hepta [b] pyrrol-8 (1H)-one derivatives (IIa-c). Application of benzoyl chloride, ethyl bromoacetate, and aminoalkyl chloride to the sodium salt of (I), formed by reaction with sodium amide, afforded the corresponding 1-benzoyl-, 1-ethoxycarbonylmethyl-, and 1-aminoalkyl-8H-cyclohepta [b] pyrrol-8 (1H)-one derivatives. As the tricyclic and tetracyclic tropone derivatives corresponding to carboline derivative, Fischer's indole cyclization reaction of 1-methyl-4-piperidone 2-troponylhydrazone hydrochloride (IX) and 1-oxo-1, 2, 3, 4-tetrahydroquinolizinium bromide 2-troponylhydrazone (XII) was examined.
5-Hydroxycyclohepta [b] pyrrol-6 (1H)-one derivatives, a compound with fused tropolone and pyrrole rings, were prepared by the use of Fischer's indole synthesis. 5-Hydrazinotropolone was not obtained from 5-aminotropolone but 5-tropolonylhydrazone derivatives (IIa-d) were obtained in one step by the use of Japp-Klingemann method. Heating with sulfuric acid and ethylene glycol was found to effect concurrent cyclization and ester exchange with the solvent ethylene glycol. By this means, 2-(2-hydroxyethoxy) carbonyl-5-hydroxycyclohepta [b] pyrrol-6 (1H)-one (IIIa) and 2-(2-hydroxyethoxy) carbonyl-3-methyl-5-hydroxycyclohepta [b] pyrrol-6 (1H)-one (IIIb) were respectively obtained from ethyl pyruvate 5-tropolonylhydrazone (IIa) and ethyl 2-oxo-butyrate 5-tropolonylhydrazone (IIb). 2-Ethoxycarbonyl-3-methyl-5-hydroxycyclo-hepta [b] pyrrol-6 (1H)-one (V), obtained by hydrolysis of (IIIb) followed by esterification, was reacted with diazomethane and formed a dimethyl compound (VI), whose structure was assumed to be 1-methyl-2-ethoxycarbonyl-3-methyl-5-methoxy-cyclo-hepta [b] pyrrol-6 (1H)-one (VIa) or its isomer (VIb).
Reaction of 2-amino-3-bromotropone (I) with active methylene compound was examined. (I) underwent condensation with active methylene compounds through its Br and NH2 groups. Reaction with diethyl malonate and ethyl cyanoacetate resulted in condensation through its CH2 and ester groups to form 3-ethoxycarbonyl- and 3-cyano-1, 3-dihydrocyclohepta [b] pyrrole-2, 8-dione (XVI), while reaction with malononitrile resulted in condensation with its CH2 and CN groups to form 2-amino-3-cyanocyclohepta [b] pyrrol-8 (1H)-one (XXI). Reaction of (I) with diethyl methylmalonate gave 3-methyl-1, 3-dihydrocyclohepta [b] pyrrole-2, 8-dione (XXII).
As a part of studies on salivary gland hormones, attempts were made to isolate a parotin-like substance from bovine serum in order to prove that parotin also existed in serum. Bovine serum was fractionated with acetone and ammonium sulfate, and passed through a column of ion exchanger, Amberlite IRC-50, from which a parotin-like substance was obtained with electrophoretic purity of 90.8%, lowering serum calcium level in rabbits of 20.07±1.32%, and having an effect on circulating leucocytes. This substance was named serum parotin. This serum parotin had maximum absorption in the ultraviolet range at 277mμ and its constituting amino acids (17 kinds) were the same as those in parotin, its sedimentation constant being S20⋅w=3.80. Examination of its N-terminal amino acid by the DNFB and pipsyl method showed it to be aspartic acid. Serum parotin is more stable to heat than parotin, there being no loss of the activity on heating at 60° for 1 hour.
It was considered that application of various proteases to serum parotin, obtained from bovine serum, might afford low-molecular substances with parotin-like activity, and trypsin, chymotrypsin, pepsin, and papain were reacted with serum parotin. Examination of the calcium-lowering and leucocyte activities of the resultant hydrolyzate showed that the calcium-lowering effect was increased than that of the control after 40 hours with trypsin or 24 hours with pepsin. Papain was found to cancel the calcium-lowering effect of serum parotin but inversely increased its action to increase the leucocytes. Chymotrypsin did not seem to change either of the effects of serum parotin. From the ultraviolet absorption and paper chromatography of the various enzymatic hydrolyzates, it was found that substances not precipitating with trichloroacetic acid increased with increasing length of incubation time.
In order to obtain a low-molecular, parotin-active substance with weak immuno-chemical antigenity by enzymatic hydrolysis of serum parotin, hydrolyzates with increased calcium-lowering activity, obtained by incubation with trypsin for 40 hours and with pepsin for 24 hours, were purified, first by acetone fractionation and by column chromatography through acidic alumina. Pepsin-fraction IIc, obtained from the 24-hour hydrolyzate of pepsin, had calcium effect of 13.91±0.33% and a leucocyte effect. Trypsin-fraction IIb, obtained from the 40-hour hydrolyzate of trypsin, had a calcium effect of 21.00±0.35% and a leucocyte effect. These substances had chemical properties similar to serum parotin but were fairly different in immunochemical properties. Both pepsin-fraction IIc and trypsin-fraction IIb had only about 1/7 the anaphylactic susceptibility of the original serum parotin when tested with guinea pig uterus sensitized with serum parotin as the antigen.
In order to see whether the serum parotin had any specificity as a salivary gland hormone, anaphylactic susceptibility, a means of immunochemical examination, was examined with guinea pig organs (Schutz-Dale reaction). Serum parotin, as well as parotin, S-parotin, and saliva parotin showed anaphylactic susceptibility with guinea pig uterus sensitized with serum parotin but bovine serum albumin, egg albumin, callicrein-like substance, or a calcium-lowering substance from a bovine kidney did not. The same result was obtained when sensitized with parotin and S-parotin, indicating that serum parotin has specificity of substances related to parotin. Dinitrophenylation and pipsylation of serum parotin resulted in the loss of this specificity but not by iodination.
In order to determine salivary gland hormone specificity of serum parotin and for its determination, precipitation reaction of serum parotin was examined with rabbit antiserum. Parotid hormonal effect of serum parotin is affected by its antiserum, especially its chief effect of lowering the serum calcium level, which is specifically neutralized, but its leucocyte effect is not affected to a great extent. Precipitin test in agar of Ouchterlony indicated that all substances related to parotin, such as parotin, S-parotin, serum parotin, and saliva parotin, show cross reaction. Serum parotin and S-parotin undergo specific and quantitative precipitation with the corresponding antiserum in a range of 10-15γ and this fact showed that immunochemical determination of serum parotin is possible.
Reaction of 1, 1, 3, 3-tetraalkoxypropane with guanidine salts and N1-amidino-N4-acetylsulfanilamides afforded 2-aminopyrimidine and N1-2-pyrimidinylsulfanilamide. The reaction of the former substances was carried out with alcohols as the solvent and saturation of hydrogen chloride in the cold. The latter reaction was carried out with glacial acetic acid as the solvent and by heating the solution of two reactants over a long period. The reaction of 2 moles of urea and 1, 1, 3, 3-tetraalkoxypropane in the presence of dil. hydrochloric acid with heating was found not to give a single substance.
1, 1, 3, 3-Tetraalkoxypropane and 1, 1, 3, 5, 5-pentaalkoxypentane are both obtained by the reaction of vinyl ethers and orthoformic acid in the presence of a Friedel-Crafts type acid catalyst, and the pentaalkoxyl derivative can also be obtained by reaction of the tetraalkoxyl derivative with vinyl ether, using the same catalyst. This synthesis of pentaalkoxypentane from the tetraalkoxyl derivative is described. Utilization of these two kinds of compounds was found in the formation of 2-aminopyrimidine by heating the tetraalkoxypropane and guanidine in the presence of ammonium acetate and of pyridine by heating pentaalkoxypentane and ammonia.
Hydrolysis of 1, 1, 3, 5, 5-pentamethoxypentane with approximately four times the theoretical amount of water and under mild conditions gives 2, 4, 6-trimethoxytetrahydropyran. If the amount of water used in this hydrolysis is increased to 10 folds and hydrolyzed with a mineral acid, 4-hydroxy-1, 3-butadiene-1-carboxaldehyde is formed, which can be separated as a crystalline sodium salt by addition of conc. sodium hydroxide solution. Catalytic reduction of acyl derivative of this substance affords 5-acyloxyvaleraldehyde, which is considered to be a useful starting material for the synthesis of dl-lysine.
Preparation of bromo derivatives of 1, 1, 3, 3-tetraälkoxypropane was examined. By careful treatment of hydrogen bromide, formed as a by-broduct during bromination, with ammonia in the cold, bromination with bromine afforded 2-bromo-1, 1, 3, 3-tetraalkoxypropane in 77.2% yield. Catalytic reduction of 1, 1, 3, 5, 5-pentaalkoxypentane over palladium-charcoal, with preliminary saturation of hydrogen chloride in the pentane derivative and reaction at 31° for 12.5 hours, afforded 1, 1, 5, 5-tetramethoxypentane in 46.3% yield.
The known process for synthesis of 2-chloroethane-1-carboxaldehyde acetal calls for addition of chlorine in vinyl ether to form 1, 2-dichloroethyl ether and its acetalization with alcohol but the yield is low when using lower alkyl ether. An attempt was made to improve this process, and addition of alkyl hypochlorite to vinyl ether and reaction of chlorine to vinyl ether in the presence of alkaline substance, such as sodium carbonate, and alcohol in the cold were found to give a good result. The yield of 2-chloroethane-1-carboxaldehyde acetal was markedly improved and that of methyl acetal reached over 80%.
In the addition reaction of sulfur halide or its alkyl and aralkyl derivatives with vinyl ethers, acetalization of the addition compounds with alcohols afforded bis (2, 2-dialkoxyethyl) sulfide in the case of sulfur halide, and 2-alkyl- or 2-aralkyl-thioacetal in the case of alkyl- or aralkylsulfenyl chloride.
Reaction of vinyl ether and acrolein to form 2-alkoxy-3, 4-dihydro-2H-pyran and introduction of chlorine in the cold, in the presence of sodium carbonate and alcohol, afforded 2, 6-dialkoxy-3-chlorotetrahydropyran in ca. 72% yield. Its oxidation with nitric acid gave 2-chloroglutaric acid in 74% yield. Reaction of vinyl ether and carbon tetrachloride, with benzoyl peroxide as a catalyst, and acetalization of its product gave 3, 3, 3-trichloropropionaldehyde acetal. Catalytic reduction of this acetal over palladium-charcoal in ammonia alkalinity afforded 3, 4-dichloro-1, 1, 6, 6-tetraalkoxy-3-hexene. 3, 3, 4, 4-Tetrachloro-1, 1, 6, 6-tetraälkoxyhexane was also obtained from this reaction according to the amount of ammonia used.
Synthesis of isoquinolines possessing 2-picolyl in 1-position was carried out, in order to see if it were possible to effect cyclization of the acid amide compounds by the Bischler-Napieralski reaction and to examine pharmacological activity of the synthesized isoquinolines. Starting with 2-picoline, ethyl 2-pyridineacetate (I) was prepared and (I) was derived through the hydrazide (II) to its azide (III). Condensation of this azide (III) and an amine (IV) afforded the acid amide (V) whose cyclization with phosphoryl chloride alone did not furnish the desired isoquinoline compound (VI). Condensation of the ester (I) and the amine (IV) was attempted by their direct fusion and N-(α-methyl-β-methoxy-3, 4-methylenedioxyphenethyl)-2-(2-pyridyl) acetamide (V) was obtained. Isoquinoline cyclization of this amide (V) by the Bischler-Napieralski reaction using phosphoryl chloride alone finally afforded the desired 1-(2-pyridylmethyl)-3-methyl-6, 7-methylenedioxyisoquinoline (VI).
Five kinds of pyrimidine derivatives (VII) substituted in 2-position with phenyl, o-tolyl, p-tolyl, p-nitrophenyl, and p-bromophenyl groups were prepared, following the synthesis of 2-amino-4-methyl-5-ethoxycarbonylpyrimidine (I). 2-Ethoxymethyleneacetoacetate (III) was prepared from ethyl acetoacetate. Five kinds each of nitriles (IV), imidoethers (V), and amidine base hydrochlorides (VI) were prepared from aromatic primary amines such as aniline, o-toluidine, p-toluidine, p-nitroaniline, and p-bromoaniline. Condensation of the amidines (VI) with the ester (III), in the presence of sodium ethoxide as the condensation agent, resulted in smooth reaction to afford the corresponding esters (VII: R=C2H5). Hydrolysis of these esters (VII) by the usual method gave the corresponding free salts (VII: R=H). In the series of this work, condensation of acetamidine hydrochloride and the ester (III) failed to afford the pyrimidine derivative.
Application of excess hydrazine hydrate to 2-phenyl-, 2-o-tolyl-, 2-p-tolyl, 2-p-nitrophenyl-, and 2-p-bromophenyl-4-methyl-5-ethoxycarbonylpyrimidine (Ia-Ve) in dehyd. ethanol afforded the corresponding 5-pyrimidinecarboxylic acid hydrazides (VI-X). These hydrazides were reacted with acetic anhydride, acetone, or acid chlorides like benzoyl, anisoyl, and tosyl chlorides, and aromatic aldehydes like vanillin and piperonal, with a suitable condesation agent in a suitable solvent and the following 15 kinds of product were obtained: 1-Acetyl-, 1-benzoyl- and 1-tosyl-2-(2-phenyl-4-methyl-5-pyrimidinecarbonyl) hydrazine, 1-acetyl-, 1-p-methoxybenzoyl, and 1-tosyl-2-(2-o- and -p-tolyl-4-methyl-5-pyrimidinecarbonyl) hydrazine, 1-acetyl-2-(2-p-bromophenyl-4-methyl-5-pyrimidinecarbonyl) hydrazine, 2-phenyl-4-methyl-5-pyrimidinecarboxylic acid isopropylidenehydrazide, vanillidenehydrazide, and piperonylidenehydrazide, and 2-p-methoxyphenyl-4-methyl-5-pyrimidinecarboxylic acid vanillylidenehydrazide.