Coevolution and Complex Chemical Interactions

Abstract Although relatively recent, peach culture has grown great in our country due to the special quality of the fruit, its very complex chemical composition and the large production that can be obtained without much effort. Peach is a species slightly adapted to our climatic conditions, suffers from winter frost, but can provide productive and long productions of 10-15 years.

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Steric Control of Complex Chemical Reactions

10.21236/ada608820 ◽

2014 ◽

Author(s):

Kopin Liu

Keyword(s):

Chemical Reactions ◽

Complex Chemical ◽

Complex Chemical Reactions ◽

Steric Control

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Large qualitative models of complex chemical and bioengineering processes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19912107 ◽

1991 ◽

Vol 56 (10) ◽

pp. 2107-2141 ◽

Cited By ~ 5

Author(s):

Mirko Dohnal

Keyword(s):

Case Studies ◽

Chemical Process ◽

Ad Hoc ◽

Chemical Reactor ◽

Theoretical Background ◽

Qualitative Model ◽

Complex Chemical ◽

Practical Applications ◽

Qualitative Models ◽

Decomposition Principle

Qualitative model is a theoretical background of commonsense. Complex qualitative models can have prohibitively many solutions (qualitative states). Therefore a qualitative analogy of such classical quantitative tools as e.g. the decomposition is developed. Practical applications of decomposition principle is nearly always ad hoc. Therefore two case studies are presented in details, a chemical process (mixer, chemical reactor, separator) and an anaerobic fermentor.

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On physico-chemical interactions between daunomycin and nucleic acids

Biochimica et Biophysica Acta (BBA) - Nucleic Acids and Protein Synthesis ◽

10.1016/0005-2787(65)90539-3 ◽

1965 ◽

Vol 103 (1) ◽

pp. 25-49 ◽

Cited By ~ 287

Author(s):

E. Calendi ◽

A. Di Marco ◽

M. Reggiani ◽

B. Scarpinato ◽

L. Valentini

Keyword(s):

Nucleic Acids ◽

Chemical Interactions ◽

Physico Chemical

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Reactivity of Aliphatic and Phenolic Hydroxyl Groups in Kraft Lignin towards 4,4′ MDI

Molecules ◽

10.3390/molecules26082131 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2131

Author(s):

Leonardo Dalseno Antonino ◽

Júlia Rocha Gouveia ◽

Rogério Ramos de Sousa Júnior ◽

Guilherme Elias Saltarelli Garcia ◽

Luara Carneiro Gobbo ◽

...

Keyword(s):

Experimental Work ◽

Chemical Structure ◽

31P Nmr ◽

Kraft Lignin ◽

Hydroxyl Group ◽

Hydroxyl Groups ◽

Diphenylmethane Diisocyanate ◽

Complex Chemical ◽

Heterogeneous Reactivity ◽

Phenolic Hydroxyl Groups

Several efforts have been dedicated to the development of lignin-based polyurethanes (PU) in recent years. The low and heterogeneous reactivity of lignin hydroxyl groups towards diisocyanates, arising from their highly complex chemical structure, limits the application of this biopolymer in PU synthesis. Besides the well-known differences in the reactivity of aliphatic and aromatic hydroxyl groups, experimental work in which the reactivity of both types of hydroxyl, especially the aromatic ones present in syringyl (S-unit), guaiacyl (G-unit), and p-hydroxyphenyl (H-unit) building units are considered and compared, is still lacking in the literature. In this work, the hydroxyl reactivity of two kraft lignin grades towards 4,4′-diphenylmethane diisocyanate (MDI) was investigated. 31P NMR allowed the monitoring of the reactivity of each hydroxyl group in the lignin structure. FTIR spectra revealed the evolution of peaks related to hydroxyl consumption and urethane formation. These results might support new PU developments, including the use of unmodified lignin and the synthesis of MDI-functionalized biopolymers or prepolymers.

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Paramagnetic solid-state NMR assignment and novel chemical conversion of the aldehyde group to dihydrogen ortho ester and hemiacetal moieties in copper(ii)- and cobalt(ii)-pyridinecarboxaldehyde complexes

RSC Advances ◽

10.1039/d1ra02512k ◽

2021 ◽

Vol 11 (33) ◽

pp. 20216-20231

Author(s):

Ayelén F. Crespi ◽

Verónica M. Sánchez ◽

Daniel Vega ◽

Ana L. Pérez ◽

Carlos D. Brondino ◽

...

Keyword(s):

Solid State ◽

Solid State Nmr ◽

Nmr Assignment ◽

Cobalt Complexes ◽

Chemical Conversion ◽

Aldehyde Group ◽

Ortho Ester ◽

Complex Chemical ◽

Chemical Functionalization

The complex chemical functionalization of the aldehyde group was elucidated in copper and cobalt complexes for 4- and 3-pyridinecarboxaldehyde ligands.

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