ChemInform Abstract: A New Synthesis of N-Acetyl-4-deoxy-D-neuraminic Acid (I).

ABSTRACT Several chemical differences between FSH, LH and HCG have been reported: thus LH and HCG are richer in proline than FSH and FSH and HCG contain more N-acetyl neuraminic acid than LH. Sub-units of LH are formed by treatment with urea, guanidine or acid. HCG also may contain two sub-units. The sub-units from LH are biologically inert but retain their immunological activity: biological activity is restored when the sub-units are incubated together. There is much evidence from chemical and enzymic reactions that antigenic groups are distinct from those parts of the molecule essential for biological activity. N-acetyl neuraminic acid and probably other carbohydrates in FSH and HCG are not involved in immunological activity but are necessary for biological activity. Histidine, methionine and possibly cysteine appear to be essential for biological but not immunological activity of FSH, while tryptophan and possibly tyrosine are not essential for either. A few highly specific antisera to gonadotrophins have been prepared in rabbits and guinea pigs to crude antigens: there is no evidence that purified antigens are more likely to produce specific antisera. Differences in the immunological reactivities of urinary compared with pituitary gonadotrophins have been observed both by radioimmunoassay and by the complement fixation technique. The latter may be particularly useful for detecting structural differences in the hormones.

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A New Synthesis and Analysis of Silica Nanowire Periodically Wrapped by Nano-spheres

Journal of Inorganic Materials ◽

10.15541/jim20150512 ◽

2016 ◽

Vol 31 (5) ◽

pp. 523

Author(s):

MA Hong-Bing ◽

BAI Hua ◽

XUE Chen ◽

TAO Peng-Fei ◽

XU Qun-Feng ◽

...

Keyword(s):

New Synthesis

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Effects on the physicochemical properties of partial substitution of Ni for Co in NixCo3-xO4 (x= 0, 0.4, 0.8) nickel-cobalt spinels using a new synthesis method (Pechini technique)

European Journal of Control ◽

10.3166/acsm.31.49-59 ◽

2006 ◽

Vol 31 (1) ◽

pp. 49-59

Author(s):

Makhtar Guene ◽

Abdou Aziz Diagne ◽

Modou Fall ◽

Mor Marème Dieng ◽

Gérard Poillerat

Keyword(s):

Physicochemical Properties ◽

Synthesis Method ◽

Partial Substitution ◽

Nickel Cobalt ◽

New Synthesis

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The Problems of Conceptualisation and Measurement of Social Capital: Towards a New Synthesis

SSRN Electronic Journal ◽

10.2139/ssrn.587241 ◽

2004 ◽

Author(s):

A.B. C. Adi

Keyword(s):

Social Capital ◽

New Synthesis

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New Synthesis of Isoindolo[2,1–b]isoquinolines. Preparation and Aqueous Bioavailability of its Silica Nanoparticles Hybrid System

Current Organic Chemistry ◽

10.2174/1385272819666150410004957 ◽

2015 ◽

Vol 19 (13) ◽

pp. 1292-1300 ◽

Cited By ~ 1

Author(s):

Amelia Diaz ◽

J. Manuel Lopez–Romero ◽

Rafael Contreras-Caceres ◽

Manuel Algarra ◽

Rodrigo Rico ◽

...

Keyword(s):

Silica Nanoparticles ◽

Hybrid System ◽

New Synthesis

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A Short Synthesis of the Plant Alkaloid 4-Methyl-2,6-naphthyridine

Letters in Organic Chemistry ◽

10.2174/1570178616666181116110647 ◽

2019 ◽

Vol 16 (12) ◽

pp. 931-934 ◽

Cited By ~ 2

Author(s):

Alexandra Kamlah ◽

Franz Bracher

Keyword(s):

Pyridine Ring ◽

Cross Coupling ◽

Antirrhinum Majus ◽

New Synthesis ◽

Short Synthesis ◽

Regioselective Oxidation ◽

Key Steps

: A new synthesis of the 2,6-naphthyridine alkaloid 4-methyl-2,6-naphthyridine from Antirrhinum majus has been developed. Key steps are a regioselective oxidation of 3-bromo-4,5- dimethylpyridine to the corresponding 4-formyl derivative, and the annulation of the second pyridine ring by Suzuki-Miyaura cross-coupling using (E)-2-ethoxyvinylboronic acid pinacol ester as a masked acetaldehyde equivalent. This protocol gives the alkaloid in four steps starting from commercially available 3,4-dimethylpyridine in 15% overall yield. This annulation protocol should be useful for the synthesis of other condensed pyridines as well.

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