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  <xsd:element id="slno_ClassOfWarrantOrRightExercisePriceDescription" name="ClassOfWarrantOrRightExercisePriceDescription" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_AssetAcquisitionContingentConsiderationArrangementsEarnOutPayment" name="AssetAcquisitionContingentConsiderationArrangementsEarnOutPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="slno_ExercisablewarrantsMaximumAggregateExercisePrice" name="ExercisablewarrantsMaximumAggregateExercisePrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="slno_ScheduleOfSignificantAccountingPoliciesTable" name="ScheduleOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_WarrantsAndRightsExercisableTermFromFollowingReceiptOfUSFoodAndDrugAdministrationApproval" name="WarrantsAndRightsExercisableTermFromFollowingReceiptOfUSFoodAndDrugAdministrationApproval" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_AssetAcquisitionContingentConsiderationChangeInFairValue" name="AssetAcquisitionContingentConsiderationChangeInFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_FacilityLeasesMember" name="FacilityLeasesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_IncentiveStockOptionsMember" name="IncentiveStockOptionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_CommonStockWarrantLiabilityMember" name="CommonStockWarrantLiabilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_IssuanceOfRestrictedStockUnitsValueAndOptionExercisesUnderEquityIncentivePlan" name="IssuanceOfRestrictedStockUnitsValueAndOptionExercisesUnderEquityIncentivePlan" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="slno_WarrantsExpireTermPriorToAnniversaryDateOfIssuance" name="WarrantsExpireTermPriorToAnniversaryDateOfIssuance" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_IncreaseInOperatingLeaseLiability" name="IncreaseInOperatingLeaseLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="slno_TwoThousandTwentyTwoCommonWarrantsMember" name="TwoThousandTwentyTwoCommonWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_TwoThousandEighteenPIPEWarrantLiabilityMember" name="TwoThousandEighteenPIPEWarrantLiabilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_TwoThousandEighteenPIPEWarrantLiabilityToPurchaseCommonStockMember" name="TwoThousandEighteenPIPEWarrantLiabilityToPurchaseCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_ControlledEquityOfferingSalesAgreementMember" name="ControlledEquityOfferingSalesAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_WarrantLiabilityDisclosureTextBlock" name="WarrantLiabilityDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_UnderwrittenPublicOfferingMember" name="UnderwrittenPublicOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_PerShareExercisePriceForPreFundedWarrant" name="PerShareExercisePriceForPreFundedWarrant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="slno_ReverseStockSplitPolicyPolicyTextBlock" name="ReverseStockSplitPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_CommitmentsAndContingenciesLineItems" name="CommitmentsAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_WarrantsAndRightsImmediatelyExercisableTerm" name="WarrantsAndRightsImmediatelyExercisableTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" name="SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_CantorFitzgeraldAndCoMember" name="CantorFitzgeraldAndCoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_EssentialisIncMember" name="EssentialisIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_ClassOfWarrantOrRightWarrantsExpirationMonthAndYear" name="ClassOfWarrantOrRightWarrantsExpirationMonthAndYear" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_AssetPurchaseAxis" name="AssetPurchaseAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_ContingentReceiptUponExeriseOfWarrantsAndFuturePerformanceOfCompany" name="ContingentReceiptUponExeriseOfWarrantsAndFuturePerformanceOfCompany" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_TwoThousandTwentyInducementEquityIncentivePlanMember" name="TwoThousandTwentyInducementEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_ProceedsFromSaleOfCommonStockAndPreFundedWarrantsNetOfCosts" name="ProceedsFromSaleOfCommonStockAndPreFundedWarrantsNetOfCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_MilestonesPayment" name="MilestonesPayment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_PercentageOfProbabilityOfAchievingMilestone" name="PercentageOfProbabilityOfAchievingMilestone" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_IncreaseDecreaseInAccruedClinicalTrialSiteCosts" name="IncreaseDecreaseInAccruedClinicalTrialSiteCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_CommitmentsAndContingenciesTable" name="CommitmentsAndContingenciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_ProceedsFromSaleOfCommonStockAndCommonStockWarrantsNetOfCosts" name="ProceedsFromSaleOfCommonStockAndCommonStockWarrantsNetOfCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_GoingConcernAndManagementsPlansTextBlock" name="GoingConcernAndManagementsPlansTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_ClassOfWarrantOrRightExercised" name="ClassOfWarrantOrRightExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_PublicOfferingPricePerPreFundedWarrant" name="PublicOfferingPricePerPreFundedWarrant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="slno_LesseeOperatingLeaseExtensionExpirationMonthAndYear" name="LesseeOperatingLeaseExtensionExpirationMonthAndYear" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_LesseeOperatingLeaseCommencementMonthAndYear" name="LesseeOperatingLeaseCommencementMonthAndYear" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_UnpaidCostsForIssuingCommonStockAndPreFundedWarrants" name="UnpaidCostsForIssuingCommonStockAndPreFundedWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="slno_TwoThousandTwentyThreeTrancheBWarrantsMember" name="TwoThousandTwentyThreeTrancheBWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_WarrantsToPurchaseCommonStockMember" name="WarrantsToPurchaseCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAggregateIntrinsicValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAggregateIntrinsicValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_ProceedsFromOfferingAfterDeductingUnderwritingDiscountAndOtherEstimatedOfferingExpenses" name="ProceedsFromOfferingAfterDeductingUnderwritingDiscountAndOtherEstimatedOfferingExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_SecuritiesPurchaseAgreementMember" name="SecuritiesPurchaseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_ScheduleOfSignificantAccountingPoliciesLineItems" name="ScheduleOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_IssuanceOfRestrictedStockUnitsSharesUnderEquityIncentivePlan" name="IssuanceOfRestrictedStockUnitsSharesUnderEquityIncentivePlan" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_TwoThousandTwentyThreeTrancheAWarrantsMember" name="TwoThousandTwentyThreeTrancheAWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_TwoThousandAndTenAndTwoThousandAndTwelveConvertiblePromissoryNotesMember" name="TwoThousandAndTenAndTwoThousandAndTwelveConvertiblePromissoryNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_AccruedClinicalTrialCostsCurrent" name="AccruedClinicalTrialCostsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="slno_OperatingLeaseRightOfUseAssetIncrease" name="OperatingLeaseRightOfUseAssetIncrease" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_OtherNonCashReconcilingItems" name="OtherNonCashReconcilingItems" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_ClassOfWarrantOrRightWarrantTerm" name="ClassOfWarrantOrRightWarrantTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_OwnershipInterestPercentageofVotingRightsofStock" name="OwnershipInterestPercentageofVotingRightsofStock" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="slno_AssetPurchaseDomain" name="AssetPurchaseDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonVestedAggregateIntrinsicValueAbstract" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonVestedAggregateIntrinsicValueAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_TwoThousandAndFourteenEquityIncentivePlanMember" name="TwoThousandAndFourteenEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_TwoThousandTwentyTwoPreFundedWarrantsMember" name="TwoThousandTwentyTwoPreFundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_TwoThousandAndFourteenEquityIncentivePlanAndTwoThousandTwentyInducementEquityIncentivePlanMember" name="TwoThousandAndFourteenEquityIncentivePlanAndTwoThousandTwentyInducementEquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_UnderwriterMember" name="UnderwriterMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_CommonStockMaximumAggregatePurchasePrice" name="CommonStockMaximumAggregatePurchasePrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="slno_OperatingLeaseCostAndSubleaseIncome" name="OperatingLeaseCostAndSubleaseIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="slno_LesseeOperatingLeaseMonthAndYearOfExpiration" name="LesseeOperatingLeaseMonthAndYearOfExpiration" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="slno_PurchasePriceContingentLiabilityMember" name="PurchasePriceContingentLiabilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="slno_IncreaseDecreaseInOperatingLeaseLiabilities" name="IncreaseDecreaseInOperatingLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
</xsd:schema>
