# Talarolide A and Talaropeptides A–D: Potential Marine-Derived Therapeutic Peptides with Interesting Chemistry and Biological Activity Studied through Density Functional Theory (DFT) and Conceptual DFT

^{*}

^{†}

## Abstract

**:**

## 1. Introduction

## 2. Results and Discussion

_{2}O constitute a wonderful tool for DFT calculations that are in agreement with the Janak and Ionization Energy theorems [21,22,23,24,25]. This is equivalent to say that the MN12SX density functional has a Koopmans-complaint behavior and that the frontier orbital energies determined through its use are enough accurate for the calculation of the chemical reactivity properties that arise from Conceptual DFT.

Electronegativity | $\chi =-\frac{1}{2}(I+A)\approx \frac{1}{2}({\u03f5}_{L}+{\u03f5}_{H})$ |

Global Hardness | $\eta =(I-A)\approx ({\u03f5}_{L}-{\u03f5}_{H})$ |

Electrophilicity | $\omega $ = $\frac{{\mu}^{2}}{2\eta}=\frac{{(I+A)}^{2}}{4(I-A)}\approx \frac{{({\u03f5}_{L}+{\u03f5}_{H})}^{2}}{4({\u03f5}_{L}-{\u03f5}_{H})}$ |

Electrodonating Power | ${\omega}^{-}$ = $\frac{{(3I+A)}^{2}}{16(I-A)}\approx \frac{{(3{\u03f5}_{H}+{\u03f5}_{L})}^{2}}{16\eta}$ |

Electroaccepting Power | ${\omega}^{+}$ = $\frac{{(I+3A)}^{2}}{16(I-A)}\approx \frac{{({\u03f5}_{H}+3{\u03f5}_{L})}^{2}}{16\eta}$ |

Net Electrophilicity | $\Delta {\omega}^{\pm}={\omega}^{+}-(-{\omega}^{-})={\omega}^{+}+{\omega}^{-}$ |

^{−1}.

## 3. Materials and Methods

## 4. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Graphical sketches of the molecular structures of (

**a**) Talarolide A, (

**b**) Talaropeptide A, (

**c**) Talaropeptide B, (

**d**) Talaropeptide C and (

**e**) Talaropeptide D.

**Figure 2.**Optimized molecular structures of (

**a**) Talarolide A, (

**b**) Talaropeptide A, (

**c**) Talaropeptide B, (

**d**) Talaropeptide C and (

**e**) Talaropeptide D.

**Figure 3.**Graphical Representation of the Dual Descriptor DD of (

**a**) Talarolide A, (

**b**) Talaropeptide A, (

**c**) Talaropeptide B, (

**d**) Talaropeptide C and (

**e**) Talaropeptide D. Left: DD > 0, Right: DD < 0.

**Figure 4.**Graphical Representation of the Biological Targets for (

**a**) Talarolide A, (

**b**) Talaropeptide A, (

**c**) Talaropeptide B, (

**d**) Talaropeptide C and (

**e**) Talaropeptide D.

**Table 1.**Orbital energies, H-L gap and the KID descriptors (all in eV) for the Talarolide A and Talaropeptides A–D molecules.

HOMO | LUMO | SOMO | H-L Gap | J(I) | J(A) | J(HL) | ΔSL | |
---|---|---|---|---|---|---|---|---|

Talarolide A | −6.14 | −0.93 | −0.96 | 5.21 | 0.04 | 0.02 | 0.05 | 0.02 |

Talaropeptide A | −6.22 | −0.85 | −0.87 | 5.37 | 0.02 | 0.00 | 0.02 | 0.01 |

Talaropeptide B | −6.16 | −0.92 | −0.92 | 5.24 | 0.00 | 0.00 | 0.00 | 0.00 |

Talaropeptide C | −6.54 | −1.00 | −1.03 | 5.54 | 0.01 | 0.01 | 0.02 | 0.02 |

Talaropeptide D | −6.56 | −0.92 | −0.91 | 5.63 | 0.01 | 0.00 | 0.01 | 0.01 |

**Table 2.**Global reactivity descriptors for the Talarolide A and Talaropeptide A–D molecules (all in eV, excepting S, in eV

^{−1}).

$\mathit{\chi}$ | $\mathit{\eta}$ | $\mathit{\omega}$ | S | N | ${\mathit{\omega}}^{-}$ | ${\mathit{\omega}}^{+}$ | $\mathbf{\Delta}{\mathit{\omega}}^{\pm}$ | |
---|---|---|---|---|---|---|---|---|

Talarolide A | 3.54 | 5.21 | 1.20 | 0.19 | 2.65 | 4.50 | 0.96 | 5.46 |

Talaropeptide A | 3.54 | 5.37 | 1.17 | 0.19 | 2.57 | 4.44 | 0.90 | 5.34 |

Talaropeptide B | 3.54 | 5.24 | 1.20 | 0.19 | 2.63 | 4.50 | 0.95 | 5.45 |

Talaropeptide C | 3.77 | 5.54 | 1.29 | 0.18 | 2.25 | 4.80 | 1.03 | 5.83 |

Talaropeptide D | 3.74 | 5.63 | 1.24 | 0.18 | 2.24 | 4.70 | 0.96 | 5.67 |

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**MDPI and ACS Style**

Flores-Holguín, N.; Salas-Leiva, J.S.; Glossman-Mitnik, D.
Talarolide A and Talaropeptides A–D: Potential Marine-Derived Therapeutic Peptides with Interesting Chemistry and Biological Activity Studied through Density Functional Theory (DFT) and Conceptual DFT. *Molecules* **2023**, *28*, 6708.
https://doi.org/10.3390/molecules28186708

**AMA Style**

Flores-Holguín N, Salas-Leiva JS, Glossman-Mitnik D.
Talarolide A and Talaropeptides A–D: Potential Marine-Derived Therapeutic Peptides with Interesting Chemistry and Biological Activity Studied through Density Functional Theory (DFT) and Conceptual DFT. *Molecules*. 2023; 28(18):6708.
https://doi.org/10.3390/molecules28186708

**Chicago/Turabian Style**

Flores-Holguín, Norma, Joan S. Salas-Leiva, and Daniel Glossman-Mitnik.
2023. "Talarolide A and Talaropeptides A–D: Potential Marine-Derived Therapeutic Peptides with Interesting Chemistry and Biological Activity Studied through Density Functional Theory (DFT) and Conceptual DFT" *Molecules* 28, no. 18: 6708.
https://doi.org/10.3390/molecules28186708