Ali, Ghassan Q. et al. published their research in Journal of Molecular Structure in 2022 | CAS: 2387-23-7

1,3-Dicyclohexylurea (cas: 2387-23-7) belongs to amides. In primary and secondary amides, the presence of N–H dipoles allows amides to function as H-bond donors as well. Thus amides can participate in hydrogen bonding with water and other protic solvents; the oxygen atom can accept hydrogen bonds from water and the N–H hydrogen atoms can donate H-bonds. Amides are not in general accessible by the direct condensation of amines with carboxylic acids for two reasons: first, both components are readily deactivated by a transfer of a proton from the acid to the amine and second, the hydroxy unit on the carbonyl of the acid is a relatively poor leaving group. Nevertheless, the formation of five- and six-membered rings is often surprisingly simple provided that other factors can be brought into play to assist in the condensation.Category: amides-buliding-blocks

Non-symmetrical bent-core homologous series bearing 1,2,4-oxadiazole core with a cholesterol terminal arm: Synthesis, characterization and their liquid crystalline properties was written by Ali, Ghassan Q.;Tomi, Ivan Hameed R.. And the article was included in Journal of Molecular Structure in 2022.Category: amides-buliding-blocks This article mentions the following:

Nonsym. 1,2,4-oxadiazole derivatives with cholesteryl and alkoxy chain as end moieties exhibiting monotropic liquid crystalline behavior have been reported. The mol. structures have been confirmed by elemental anal. and spectroscopic studies. Differential scanning calorimetry (DSC) studies revealed multiple phase transitions and polarized optical microscopy (POM) investigations confirmed smectic A (SmA) and chiral nematic (N*) phases. The importance of alkyl chain length in mesophase formation is discussed. A comparison with other reported mesogenic materials possessing similar mol. structures is also discussed. In the experiment, the researchers used many compounds, for example, 1,3-Dicyclohexylurea (cas: 2387-23-7Category: amides-buliding-blocks).

1,3-Dicyclohexylurea (cas: 2387-23-7) belongs to amides. In primary and secondary amides, the presence of N–H dipoles allows amides to function as H-bond donors as well. Thus amides can participate in hydrogen bonding with water and other protic solvents; the oxygen atom can accept hydrogen bonds from water and the N–H hydrogen atoms can donate H-bonds. Amides are not in general accessible by the direct condensation of amines with carboxylic acids for two reasons: first, both components are readily deactivated by a transfer of a proton from the acid to the amine and second, the hydroxy unit on the carbonyl of the acid is a relatively poor leaving group. Nevertheless, the formation of five- and six-membered rings is often surprisingly simple provided that other factors can be brought into play to assist in the condensation.Category: amides-buliding-blocks

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics