Organic Chemistry
II. Action of organo-alkali-metallic compounds on disulphides, diselenides, carbon disulphide,
and thionylamine derivatives and synthesis of dimeric diphenylthioketen. A. Sc h o n b e r g, A.
St e p h e n s o n, H. Ka l t s c h m i t t, E. Pe t e r s e n, and H. Sc h u l t e n. III. Action of lithium phenyl on trimethylene-1 : 3-disulphide and syntheses of dichromylenes. A. Sc h o n b e r g, H. Ka l t s c h m i t t,
and H. Sc h u l t e n (Ber., 1933, 6 6, [B], 233— 236, 237— 244, 245— 250).— I. Thionaphthen is converted by Na in Et20 at 25— 30° into 2-sodio thionaphthen, transformed by C02 into thionaphthen-2-carboxylic acid, m.p. 236° (Me ester, m.p. 71— 73°). Benzildi- phenylmercaptal, CPhBz(SPh)2, similarly affords NaSPh and disodiodeoxybenzoin, identified as deoxy- benzoin, m.p. 57°. Dixanthylene and NaSPh are derived from xanthonediphenylmercaptal and CPh2:CPh2 and its Na2-derivativc from benzophen- onediphenylmercaptal. Benzaldehydebenzylmer- captal appears unaffected by Na.
II. Alkali organo-metallic compounds and di
sulphides react, S R '- S R '+ R ''X = R 'S R " + I t ,SX, fre
quently with great readiness in Et20 . Thus, Ph2S2
and LiPh afford Pli2S, b.p. 159°/16 mm., and LiSPh;
gives Ph2Se [dibromide, m.p. 145° (decomp.)] and with Li p-methoxyphcnyl affords Php-methoxyphenyl solenide \dibromide, m.p. 125° (decomp.)]. afi-Di- sodiobisdiphenylene-ethane is transformed by Ph2S2
into aB-bisdiphenyleno-ethylene, m.p. 185°; analo
gously, disodiotetraphenylethane and Et2S2 yield NaSEt and tctraphenylethylene. NPh2K and ((3- Ci0H7)2S2 yield KSC1 0H7 and (?) (3-naphthylIhioldi- plienylamine, NPh2*SC1 0H 7, m.p. 92° (decomp.), CPh3
and Ph2S2 in CGH G afford PhS-CPh3, thus indicating the partial decomp, of Ph2S2 into radicals with S1
(confii-med by the non-adherenco of Ph2S2 in C1 0H8 at 100° to Beer’s law). CS2 in Et20 is converted by Li a-naphthyl into dithio-a-naphthoic acid, identified as di-a-thionaphthoyl disulphide, m.p. 169°. CS2 and CHPh2Na give the non-cryst. diphenyldithioacetic acid, which passes at 130— 140° into dimeric diphenyl
thioketen, m.p. 257— 258°. Thionylanilino reacts vigorously with LiPh and Li a-naphthyl giving respectively benzenesulphin-anilide, m.p. 1 1 2°, and -a-naphlhylamide, m.p. 126°. These compounds are distinguished from t]ie corresponding sulphonamides by their inability to react with CH2N2, Benzene- sulphon-anilide and -P-naphthylamide, ethanesul- phonanilide, and saccharin give Me derivatives with CH2N2 and methiondianilido gives the Et-2 derivative with CHMeN2.
I l l (cf. A., 1931, 1305, 1419). The conversion of 4 : 4 : 5 : 5 - tetraphenyltrimethylene - 1 : 3-disulphide into CPh2!CPh2 by LiPh (loc. cit.) is accompanied by the production of LiSPh; the suggested scheme for the reaction is CH2<^g,^pj!2+ LiPh — y
crh>:crh,+Lis|+
[CH2:S]. 4-Thiocliromone and CH2N2 in Et20 readily yield the compound (I), decomp, above 170°, converted by LiPh into LiSPh and (?) non-cryst.
dichromylene (mixture of cis- and ¿rewis-forms). 4-Thioflavone and Cu powder in boiling PhMe afford 2 :2'-diphenylchromylcne
O-CPh '
y ° \
px®,
0
^
(I.) m.p. 224° (A.,
1931, 1305), whilst a-naphtha-4-thioilavone is trans
formed by the successive action of CH2N2 and LiPh into di-tx-naphthaflahylene, C3 8H2 10 2, m.p. 252°. Thio- xanthen and CH2N2 yield the compound C2 7H1 8S4, m.p. 16S— 170° (decomp.), transformed into dithio- xanthyleno by L iP h; dixanthylene is similarly
prepared. H. W.
Organic compounds of sulphur. X X II.
Action of sodium diphenylmethyl on diphenyl sulphoxide ; radical migration. A. Sc h o n b e r g
and A. St e p h e n s o n (Ber., 1933, 6 6, [B], 250— 252).—
Ph2SO and CHPh2Na in Et20 yield CHP1i3 (as such) and PhSONa (I) oxidised by air to PhS02N a;
CHPh2N a + P h2SO=[CH Ph2-SPh2-ONa]— >CHPh3+
PhSONa. Ph2S2 and PhSH, observed by Bergmann
292 B R IT ISH CHEM ICAL A B STR A C T S.— A .
and Tschudnovski (A., 1932, 507), aro formed by the
action of H20 on (I). H. W.
Organic compounds of mercury. V. Aryl
ation of mercuric oxide by aromatic iodoxy- compounds. A. N. Ne s m e j a n o v and L. G. Ma k a r o v a (Ber., 1933, 6 6, \B], 199— 201).— Reaction follows the course R T 02+ H g 0 — >R-H g--)-I03' and occurs in presence of every type of cold alkali (when shaken), best in that of Ag20 . It is most complete when the mixture of I 02-compound, freshly pptd. HgO, and Ag20 is heated in boiling H20 . The base can be isolated as such, but is more readily obtained as the halide. Examples cited are : HgPhBr, m.p. 275°, from P h I02 ; Hg p-tolyl bromide, m.p. 235°, from p-CrH,1M e-I02 ; Hg o-chlorophcnyl chloride, m.p.
147°, from o-G8H4ChI02 ; Hg m-chlorophcnyl chloride, m.p. 210°, from m-C6H4C H 02 ; Hg p-chlorophenyl chloride, m.p. 240°, from p-C8H4CbI02 ; Hg o-nitro- phenyl chloride, m.p. 185° ; Hg m-nitrophqnyl chloride, m.p. 236°; Hg p-nitrophenvl chloride, m.p.
265°. .. II. W.
Structural chemistry of proteins. I. Ring closure and increase in oxygen content on méth
oxylation of glycinin. A. Ki e s e l and M. Zn a m e n s k a y a (Z. physiol. Chem., 1932, 2 1 3 , 89— 109).— In the formation of glycinin hydrochloride (I) and of the Me ester hydrochloride (II) a part of the protein con
stituent undergoes change. In (I) some of the acidic groups are eliminated with removal of H20 , probably owing to internal estérification. In (II) some amide-N is eliminated and about half the weakly basic NH2-N disappears, again owing to removal of H20 . The power of combining with HC1 is not diminished. 0 enters the mol. during estérification, and lysine and tryptophan disappear, whilst arginine, tyrosine, and histidine arc decreased. A small proportion of the protein becomes sol. in the HCl-MeOH mixture.
J. H. B.
Mode of combination of proline in gelatin and collagen. M. Be r g m a n n, L. Ze r v a s, and H.
Sc h l e ic h (Collegium, 1933, 6— 9).— The 1NH groups of proline and oxyproline are involved in the peptide chains in gelatin and collagen and are the first to be freed during ereptic action. D. W.
Determination of carbon and hydrogen by the centigram method. K . Kü s p e r t (Chem. Fabr., 1933, 6, 63— 64).— Modified apparatus is described.
Cu (reduced from CuO) is used in place of P b 02 for removing oxides of N, and tho stream of 0 2 is replaced
by air. E. S. H.
Rapid determination of chlorine in organic compounds. N . M . Mi l o s l a v s k iand V. F. Ve p r i t z- k a y a (J. Appl. Chem., Russia, 1932, 5 , 860— 867).—
Combustion of an EtOH solution in a current of air, absorption of HC1 in aq. A gN 03, and titration with
KCNS are employed. Ch. A b s.
Determination of iodine in organic compounds containing selenium. F. M. Ha m e r (Analyst, 1933,
5 8 , 26— 27).— The substance is heated with fuming
H N 03 and A gN 03 at 300°. The resulting ppts. are boiled with H20 , filtered hot, and washed with boiling 20% H N 03. After drying and weighing, the A gl is dissolved in KCN to obtain the wt. of the Gooch
crucible. , T. McL.
Determination of chloroform in alcohol-water mixtures. D. N. Po p o v (Khim. Farm. Prom.,1932, 222— 224).—The EtOH concn. is adjusted to 15%, ' when CHC13 is thrown out of solution, and its vol. is measured. H tho CHC13 content is very small a known amount of light petroleum is added.
Ch. Ab s. Thermometric titration of acetaldehyde in presence of organic and inorganic acids. S. I.
Ruibest(J. Appl. Chem., Russia, 1932,5, 463— 469).—
Somiya’s method is satisfactory. Ch. Ajbs.
Behaviour of benzoyl peroxide towards amino- compounds. I. De Pa o l i n i and G. Ri b e t (Gaz- zetta, 1932, 6 2 , 1041— 1048).— With primary amines,
Bz20 2 yields B z02H and RNHBz (cf. A., 1931, 209), and with sec. amines, BzOH and R R 'N ’O B z; it may therefore be used to differentiate these. It is mixed with the amine in EtOH, and, after keeping, dilution, addition of NaOH, and boiling, Fehling’s solution is added. Reduction indicates a sec. amine (tested with NHEt2, NHPr°2, piperidine, and tetrahydroquinoline), negative reaction a primary amino (tested with lieptyl-, fsobutyl-, isoundecyl-, and benzyl-amine).
isoUndecylamine, ethylenediamine, andj semicarb- azido yielded their Bz, Bz2, and Bz derivatives, respectively, whilst N(CH2Ph) 3 gave a mixture of PhCHO and NH(CH2Ph)2,2BzOH, and NPr“ 3 gave
NHPr°, E. W. W.
Mercuro-reductive power of certain amino- acids. C. San mi. and R. Tr u h a u t (Compt. rend., 1933, 1 9 6 , 65— 67).— Of various NH2-acids tested the following reduce Nessler’s reagent in alkaline solution:
glycine, serine, histidine, tryptophan, phenyl-P-alan- ine, dihydroxyphenylalanine, proline, creatine, creat
inine, and cystine. W. 0 . K.
Test for phenols and copper. C. C. Fu l t o n.—
See this vol., 245.
Reaction of benzidine with acidic derivatives of selenium and tellurium. A . G. Kr e t o v (J. Appl.
Chem., Russia, 1932, 5 , 634— 636).—The compound formed by H2Se04 or its salts (but not H2Se03, H2T e03, or H2T e04) with benzidine, which is rather more sol. in H20 than the H2S04 compound, can be titrated with 0-1—0-2iV-alkali in presence of phenol-
phthalein. Ch. A b s.
Detection of papaverine. L. Ek k e r t (Pharm.
Zentr., 1933, 74, 24— 25).— Papaverine (0-01 g.) or the hydrochloride, dry ZnCl2 (0-02 g.), and BzCl (5 drops) on careful heating give-rose, rose-red, blood- red, and finally yellow to gold colours with a green fluorescence (yellowish-green under the quartz lamp).
Addition of 1— 2 c.c. of EtOH gives a greenish-yellow fluorescence. The reaction is sensitive to 0-02 mg. and with atropine, scopolamine, narcotino, and cryptopine only the initial red colour is formed. E. H. S.
B IO C H E M ISTR Y . 293
Biochemistry.
Comparison of metabolic respiration of eels in various stages of development. (Ml l e.) A . Ra f f y
(Compt. rend., 1933, 196, 374— 376).—Respiration (c.c. 0 2 consumed per g.-hr.) of eels in various stages of development is more rapid the smaller is the body-wt., sex being without appreciable influence. J. W. B.
Oxygen affinity of haemoglobin expressed by the constant l//e and the plasma-p,,, and the factors which may affect it. G. Li t a r c z e k, H.
Atjb er t, and I. Co s m u l e s c o (Compt. rend. Soc. Biol., 1931,106, 740— 742; Chem. Zentr., 1932, ii, 2326).
A. A. E.
Effect of temperature on the carbon dioxide absorption curve of human blood. A . J. Ei s e n- m a n (J. Biol. Chem., 1933, 99, 359— 381).— Lowering the temp, of blood with const. C02 tension increases C03" and HC03', the latter being directly proportional to the haemoglobin content. The effect of temp, on the C02 capacity of serum is 1*1 times that on whole blood. The effect on pa also depends on the haemo
globin content: anaemic blood shows a decrease, whilst normal blood shows an increase at lower temp.
H. G. R.
Absorption of ultra-violet radiation b y haemo
globin and some of its derivatives. H . E. Ho l d e n
and C. S. Hi c k s (Austral. J. Exp. Biol., 1932, 10, 219—223).— The bands observed with their heads and extinction coeffs. are as indicated. Rabbit haemo
globin (>.422-8 mu, e 123X103; X 272-0mg, e 3 7 x l0 3).
Opossum haemoglobin (X 419-5 l u , e 127 XlO3;
X 262-7 mg, e 28-2XlO 3). Denatured ox globin- haemochromogen (X 423-7 mg, e 110 X103; X 332-3 mg,
e 31-4XlO3; X 270-5 mg, e 27-7XlO3). Cyano- haemochromogen, X 435-0 mg, e 9 1 -0 x l0 3; X 338-0 mg, e 24-7XlO3; X 264-0 mg, e 24-7XlO3). Reduced haematin (X 393-5 mg, e 44-1 XlO3; X 264-6 m g , e
14-7X lO 3). W. O. K.
Mol. wts. of globin of different haemoglobins G. S. Ad a i r, (Mm e.) Ad a i r, J. Ro c h e, and (Mm e.) Ro c h e (Compt. rend., 1932, 195, 1433— 1435).—The apparent mol. wts. of globin, paraglobin (denatured globin), and haemoglobin, determined osmometrically, are 37,000, 99,000, and 67,000, respectively, for the ox, and 29,000, 63,000, and 65,000 for the horse. Globin and paraglobin are in equilibrium with polymerides in
solution. A. C.
Detection of blood by 2 : 7-diaminofluorene hydrochloride. J. Sc h m i d t and M. Ei t e l (Ber., 1932, 65, [jB ], 1867).— The reagent (A., 1932, 242) does not become discoloured if the pure salt is dissolved in H20 which has been boiled and allowed to cool in C02
and the solution is again saturated with C02 and pre
served in a tightly-closed vessel. H. W.
Difficulties encountered in obtaining a satis
factory Wright stain [for blood]. H. J. Co n n and L. A. Ma r g o l e n a(Stain Tech., 1933,8,35— 36).—It is important to work at the correct [H ’j and to use pure
MeOH. H. W . D.
Solubility of plasma-proteins. I. Depend
ence on salt and plasma concentrations in con
centrated solutions of potassium phosphate.
A. M . Bu t l e r and H. Mo n t g o m e r y" (J. Biol. Chem., 1933, 99, 173— 195).— Solubility curves of horse and human serum-proteins in varying concns. of an equimol. solution of K2H P 04 and K H2P 04 at p n 6-5 and 25° are plotted. The fibrinogen complex has a negligible solubility in 1-2M solution. The human plasma curve shows no break corresponding with the separation of the pseudoglobulin complex, whilst a larger content of albumin is indicated. By assuming a linear relationship between‘ the log. of the protein solubility and tho salt concn. for each portion of the curve, the concn. of tho less sol. plasma-protein fractions at the concns. selected for fractional pptn.
and the concn. of the individual proteins are compared with vals. from the analysis of ppts. obtained by x and £ vol.-% saturation with (NH4)2S04 at 25° and 14-5 and 22% Na2S04 at 37°. H. D.
Effect of water ingestion on ratio of albumin to globulin in blood-serum. C. Au g u s t e (Compt.
rend. Soc. Biol., 1932, 111, 718— 719).— The ingestion of 500 c.c. of distilled H 20 produced alterations in the ratio of albumin to globulin in tho blood-serum. The changes thus produced varied from subject to subject, but, on the whole, tho increase in tho ratio paralleled that of the hydrmmia. Nu t r. Ab s.
Critical temperature of serum. VII. Elec
trical conductivity of serum in relation to tem
perature. P. Le c o m t e d u No u y (Ann. Inst.
Pasteur, 1933, 50, 127— 142).—Above 55° a fixation of II20 by the serum-proteins occurs, which gives rise to (a) an increase in salt concn. with an increase in K, and (6) an increase in the vol. of the non-conducting mols., with a consequent reduction in K. Theoretic
ally the latter eSect should predominate, as it does qualitatively, but to an extent > that indicated by existing theories. With globulin suspensions adsorp
tion of electrolytes occurs, but this does not explain tho results where the mols., although subject to swelling, still remain in solution. P. G. M.
Micro-determination of copper and its applic
ation to blood, bsemocyanin, and animal tissues.
R. Gu i l l e m e t (Bull. Soc. Chim. biol., 1932, 14, 1350— 1385).—The technique of a method for the determination of upwards of 0-01 mg. Cu with an error of 3% is described. From the aq. H N 03 solution of tho ash of tho material to be examined, Fe is re
moved by C5H 5N and Cu pptd. in the presence of Ni as Cu(OH)2. An aq. H2S04 solution of the latter is electrolysed and the Cu deposit determined volu- metrically by the phosphomolybdie acid method. Tho Cu content of tho blood of various animals and its distribution between the corpuscles and the plasma is determined. Determinations of the Cu in the spleen and liver of dogs are made, and, in the case of the liver, the variations in the Cu content caused by bleeding and after ingestion of Cu. A modification of the method is used to determine the Cu in tho hsemo- cyanin of Helix pomatia, Maia squinado, and Cancer pagurus. In these cases the no. of atoms of Cu is shown to be equal to no. of atoms of combined 0 .
A. L.
294 B R ITIS H CHEM ICAL A B STR A C T S.— A .
Determination of magnesium in blood with 8-hydroxyquinoline. C. Bo m s k o v (J. Biol. Chem., 1932, 9 9 , 17— 18).— A comparison of the .author’s method (this vol., 35) with that of Greenberg and Mackoy (ibid., 764). The Mg content of blood ranged from 1-7 to 2-6 mg. per 100 c.c. for normal men, from 1-3 to 2-3 mg. for normal children, and from 0-8 to 1*1 mg. for children with florid rickets. H. G. R.
Determination of magnesium in blood with 8-hydroxyquinoline. D. M. Gr e e n b e r g and M. A.
Ma c k e y (J. Biol. Chem., 1932, 9 9 , 19).— Polemical (cf. preceding abstract). H. G. R.
Individual variation in serum-calcium in normal men and women. R . E. Bo y n t o n and E. M. Gr e i s h e e u e r (Proc. Soc. Exp. Biol. Med., 1931,
2 8 , 907— 913).—Serum-Ca in the morning was : men 10-31, women 10-01 mg. (average) [per 100 c.c. ?].
In normal women vals. decreased in the menstrual or post-menstrual period. Ch. A b s .
Is there an unknown compound of the nature of calcium citrate present in the blood ? D. M.
G r e e n b e r g and L. D. G r e e n b e r g (J. Biol. Chem., 1932, 9 9 , 1— 15).—There is no definite evidence of the existence of an org. citrate-like compound of Ca
in blood. H. G. R.
Reciprocal relationship of calcium and in
organic phosphorus of the blood of sheep.
A. H. H. Fr a s e r (Biochem. J., 1932, 2 6 , 2166—
2168).— In sheep under outdoor conditions, fed on a basal ration deficient in Ca, or such a ration sup
plemented with cod-liver oil, there is a relative constancy of the C a x P product. S. S. Z.
Effect of anticoagulants on the determination of inorganic phosphate and protein in plasma.
0 . H. Ga e b l e r (J. Biol. Chem., 1932, 9 9 , 99—
107).— Plasma always contains less inorg. phosphate and less total N than serum, due to HaO being drawn from the cells. With native plasma as standard, the inorg. phosphate of oxalate-plasma is low and that of serum is high. Oxalate-plasma left in contact with the cells at 10° for 5 hr. shows no change.
Fluoride interferes with the Benedict-Theis and Fiske- Subbarow reactions ; tins is prevented by A1CL.
H. G. R.
Reactions of lead compounds with serum and serum-models. M. Jowett(Biochem. J., 1932, 26, 2108—2122).—When C03" is the only precipitant ion PbC03 is formed. In presence of P 0 4" ' (and Cl') the product is Pb5CI(P04)3. When Ca is also present, the product approximates to
Pb5C1 (PO.j)3,Ca -Cl (P 0 4)3. Pb ion reacts very rapidly, but the union of Ca is less rapid than that of Pb and may be incomplete under unfavourable conditions.
Solubility and extent of surface determine the rate
~^if reaction of solid Pb compounds with P 0 4" '. An approx. val. is obtained for the solubility product of PbC03 at 37-5°. The solubilities in serum of PbC03, PbH P04, Pb3(P 04)2, and P b5Cl(P04 ) 3 are calc.; the last compound is the least sol.
S. S. z.
M icro-colorim etric determ ination of iodine in b lo o d . R. G. Tu r n e r and M. Z. We e k s (J. Amer.
Chem. Soc., 1933, 55, 254— 258).— The method
previously described (A., 1930, 1463) is satisfactory provided I-free K2CO;i (or KOH), H2S04 containing
< 0-00008% Fe, and EtOH purified by Castille and Henri’s method (A., 1924, ii, 581) are used.
H. B.
Volatile chlorine of blood. S. Mo r r is and N.
Mo r r is (Biochem. J., 1932, 2 6 , 2015—2020; cf.
A., 1931, 248).— The presence of 02 is essentiaT'for the loss of Cl to take place. The heating of an olive oil-NaCl mixture (I) at > 100° leads to loss of Cl..
There is a close similarity between blood and (I) as far as the loss of Cl is concerned, except that heat is required in the latter case, whilst drying in a desiccator is sufficient to produce a loss of the Cl complex in the former case. Org. Cl can be extracted from blood by removing H20 with COMe2 and Et20 and sub
sequent extraction by ah E t0 H -E t20 mixture.
S. S. z.
Method for measuring cholesterol. P. G.
Sc h u b e (J. Lab. Clin. Med., 1932, 1 8 , 306— 309).—
The green colour obtained with cholesterol (I), H2S04, and Ae20 and employed in the usual colorimetric determination of (I), on keeping at 2 0° in the dark for 12— 24 hr. fades into a yellow colour. Tables show that colorimetric determination of (I) using the yellow colour for comparison gives much greater accuracy than when the green is used. A table also compares the yellow and green vals. for the (I) contents of a no. of samples of blood. Nu t r. Ab s.
Effect of infra-red rays on blood-cholesterol.
S. Ma l c z y n s k i (Compt. rend. Soc. Biol., 1932, 1 1 0 ,
808— 810; Chem. Zentr., 1932, ii, 1797).— Energetic irradiation has no effect, but weaker prolonged irradiation causes a transient rise. A. A. E.
Protein-lipin combinations in blood and body- fluids. I. Normal human and dog plasma and horse serum. M. E. Tu r n e r and R. B. Gi b s o n (J.
Clin. Invest., 1932, 1 1 , 735— 746).— Fatt}' acids, phospholipins, and cholesterol were determined in the protein fractions. 50% of the lipins were co- pptd., particularly by the globulins. Ch. Ab s.
M ic r o -d e t e r m in a t io n of p h o s p h a tid e s in b lo o d . S. Ka t s u r a, T. Ha t a k e y a m a, and K . Ta j i m a (Bio
chem. Z., 1933, 2 5 7 , 22— 31; cf. A., 1931, 858).—
Lecithin is quantitatively pptd. when a saturated solution of CaCl2 in COMe2 is added to a COMe2
solution of a fat mixture. The method described, which is based on this fact, makes possible the deter
mination of 0 - 1 mg. of lecithin with an error of ± 2—
3% and the determination of the phosphatide con
tent of 0-15— 0-2 c.c. of blood with an error of ±2—
5% . W. McC.
Effect of ingestion of a large amount of fat and of a balanced meal on the blood-lipins of normal man. E. B. Ma n and E. F. Gi l d e a (J. Biol. Chem., 1932, 99,61— 60).—Vals. for the distribution of serum - lipins of normal individuals are given. Ingestion of 3 . 5—4 - 0 g. of fat per kg. produces a marked rise in serum-fatty acids and a moderate increase in phospholipins. Ingestion of a balanced meal con
taining at least 0 - 6 g. of fat per kg. produces a rise
in serum-fatty acids. H. G. R.
B IO C H E M ISTR Y . 295
Modification of the Stoddard and Drury method for the determination of fatty acids in blood- serum. E. B. Ma n and E. P. Gl l d e a (J. Biol.
Chem., 1932, 99, 43— 60).—A titrimetric method for the determination of serum-fatty acids (exclusive of very unsaturated or H20-sol. fatty acids), based on that of Stoddard and Drury (A., 1930, 103), is
described. H. G. R.
Optical activity of blood-filtrates. II. Effect of acidity and the relation between rotation and reduction values. H. N. Na u m a n n (Biochem. Z., 1933, 257, 32—40; cf. A., 1932, 1053).—The rotation of the blood-filtrate (I) obtained in the method of Folin and Wu increases with the degree of acidity, reaching a max. (dextro) at pa “ —0-7,” the reducing power meanwhile remaining unaffected. The increase (II) is due to alteration of the non-sugars, since it also occurs after removal of the sugar as well as in normal urine and does not occur in the filtrates from Zn and Cd treatment. Very probably (II) is due partly to liberation of org. ¿-acids from Z-salts and partly to hydrolysis of /-polypeptides and glycur- onates, whilst mutarotation also causes slight in
creases or decreases. In the (I) of normal persons and in that of diabetics the max. ¿-rotation of the filtrates corresponds with the reducing powers as measured by the Hagedorn and Jensen method.
The results indicate that (I) contains the usual equilibrium mixture of glucose modifications and not a special modification. W. McC.
Interference of non-glucosidic substances, par
ticularly lactic acid, on the measurement of the optical rotatory power of blood-sugar. J.
Th o m a s (Bull. Soc. Chim. biol., 1932, 14, 1279—
1289).— The change with change of pn in the rotatory power of dialysed blood cannot be due to the presence of substances known to be in the blood, such as NH2- acids and lactic acid, because the change is too great, and still persists after the extraction of the lactic acid. The change is not observed in the dialysed blood of diabetics, but reappears after the administra
tion of insulin. These facts are considered to indicate that the phenomenon is due to a change in the equilibrium of two forms of glucose, or the presence of an unstable combination of this and an unknown substance, or to some unknown product of carbo
hydrate metabolism. A. L.
Distribution of sugar in blood and the perme
ability of red blood-corpuscles. L. Mo s o n y i (Bio
ability of red blood-corpuscles. L. Mo s o n y i (Bio