6. Current Convertible Notes Payable and Other Notes Payable. As of March 31, 2022 and December 31, 2021, the amount of convertible and other notes payable totaled $4,389,931 and $3,589,931, respectively. The details of the convertible notes payable and other notes payable are shown in the table below:

Notes:

(1) On March 17, 2022, we executed a Promissory Note Extension Agreement with Ainos KY in which the due dates for certain convertible notes enumerated as #12.21 to #24.21 issued by the Company to Ainos KY were extended to February 28, 2023. The total unpaid principal for these extended period convertible notes amount to $3,000,000 in the aggregate.

(2) On March 11, 2022, the Board approved a Non-Convertible Note dated March 4, 2022 in favor of Ainos KY with a principal amount of $800,000, interest of 1.85% per annum on unpaid principal and accrued interest, and a maturity date of February 28, 2023. The Note includes standard provisions for notice, default, and remedies for default.

All of the aforementioned convertible promissory notes and other notes payable are unsecured and due on demand upon maturity. The Company may prepay the notes in whole or in part at any time. The holder of convertible notes has the option to convert some or all of the unpaid principal and accrued interest to our common voting stock.

The total interest expense of convertible notes payable and other notes payable for the three months ended March 31, 2022 and as of December 31 2021 was $15,883 and $11,897 respectively; the cumulative related accrued interest as of March 31, 2022 and December 31, 2021 were $44,556 and $28,673, respectively.

4. Convertible Notes Payable and Other Notes Payable

All convertible and other notes payable were issued either as a result of financing or deferred compensation provided by executives of the Company. As of December 31, 2021 and December 31, 2020, convertible and other notes payable totaled $3,589,931 and $953,001, respectively; including notes payable for related parties totaling $3,505,931 and $805,001, respectively. Refer to disclosure in Note 5 below.

The details of the convertible notes payable and other notes payable are shown in the table below:

All of the aforementioned convertible promissory notes and other notes payable are unsecured and due on demand upon maturity. The Company may prepay the notes in whole or in part at any time. The Payee has the option to convert some or all of the unpaid principal and accrued interest to our common voting stock.

The convertible promissory notes are convertible on demand. The following convertible notes due to Stephen T. Chen - Notes 3.19, 4.19, 6.20, 7.20, 10.21, and 11.21 -- with a total principal and accrued interest amount of $372,988 were assigned by the holder to Top Calibre Corporation, a British Virgin Islands corporation, and subsequently converted in common stock of our company at a conversion price of $0.25 per share on December 27, 2021. No convertible notes were assigned in 2020.

During 2021, the Company received funding from Dr. Stephen T. Chen and Ainos KY totaling $214,420 and $3,000,000, respectively. Amounts owed to Dr. Stephen T. Chen of $150,000 were repaid. In 2020, the Company received funding from Dr. Stephen T. Chen totaling $373,976.

Note holders, i2China Management Group, LLC (“i2China”) and Dr. Stephen T. Chen (together the “Payees”), agreed to waive their rights pertaining to the conditional term “Annual Interest Rate on Matured, Unpaid Amounts: 10% per annum, compounded annually of Convertible Notes” in regards to interest charged on unpaid amounts following maturity for all of their respective notes. The Company and the Payees agree that the originally agreed annual interest rate will continue to be valid for any unpaid amounts after maturity. The amended terms of the above convertible notes and other notes payable were made during on September 1, 2021. Interest waived totaled $45,875.

The total interest expense for 2021 and 2020 totaled $21,727 and $10,702 respectively; the cumulative related accrued interest as of December 31, 2021 and 2020 were $28,673 and $24,196, respectively.